[Illustration]

SCIENTIFIC AMERICAN SUPPLEMENT NO. 385

NEW YORK, MAY 19, 1883

Scientific American Supplement. Vol. XV. , No. 385. 

Scientific American established 1845

Scientific American Supplement, $5 a year. 

Scientific American and Supplement, $7 a year. 

 * * * * *

TABLE OF CONTENTS. 

I. NATURAL HISTORY. --Fishes of Cuban Waters. 

 Panax Victoriæ. --1 Illustration. 

 A Note on Sap. By Prof. ATTFIELD. 

 The Crow. --Illustration. 

 The Praying Mantis and its Allies. --Illustration. 

 May Flies. --2 illustrations. 

II. TECHNOLOGY. --A Quick Way to Ascertain the Focus of a Lens. --1 diagram. 

 The History of the Pianoforte. By A. J. HIPKINS. --Different parts of a pianoforte and their uses. --Inventor of the instrument and his "action. "--First German piano-maker. --Square pianos. --Pianos of Broadwood, Backers, Stodart, and Erard. --Introduction of metal tubes, plates, bars, and frames. --Improvements of Meyer, the Steinways, Chickerings, and others. --Upright pianos. --Several figures. 

III. MEDICINE AND HYGIENE. --The Poisonous Properties of Nitrate of Silver and a Recent Case of Poisoning with the Same. By H. A. MOTT, Jr. 

 Tubercle Bacilli in Sputa. 

 Malaria. By Dr. JAMES H. SALISBURY. --VIII. Local observations. --Effect of the sun on ague plants. --Investigations into the cause of ague. --Notes on marsh miasm. --Analysis of malari a plant. --Numerous figures. 

IV. ENGINEERING. --Torpedo Boats. --Full page illustration. 

 Pictet's High Speed Boat. --Several figures and diagrams. 

 Initial Stability Indicator for Ships. --4 figures. 

V. ELECTRICITY, LIGHT, AND HEAT. --Scrivanow's Chloride of Silver Pile. --2 figures. 

 On the Luminosity of Flame. 

VI. CHEMISTRY. --New Bleaching Process, with Regeneration of the Baths Used. By M. BONNEVILLE. 

 Detection of Magenta, Archil, and Cudbear in Wine. 

VII. ARCHITECTURE. --The Pantheon at Rome. 

VIII. MISCELLANEOUS. --The Raphael Celebration at Rome. --3 Illustrations. 

 Great International Fisheries Exhibition. --1 figure. 

 Puppet Shows among the Greeks. --3 illustrations. 

 * * * * *

THE RAPHAEL CELEBRATION AT ROME. 

The most famous of Italian painters, Raffaele Sanzio, whom the worldcommonly calls Raphael, was born at Urbino, in Umbria, part of the PapalStates, four hundred years ago. The anniversary was celebrated, on March28, 1883, both in that town and in Rome, where he lived and worked, andwhere he died in 1520, with processions, orations, poetical recitations, performances of music, exhibitions of pictures, statues, and busts, visits to the tomb of the great artist in the Pantheon, and withbanquets and other festivities. The King and Queen of Italy were presentat the Capitol of Rome (the Palace of the City Municipality) where onepart of these proceedings took place. 

[Illustration: SKELETON OF RAPHAEL AS FOUND IN HIS TOMB IN THE PANTHEON, IN 1833. ]

At ten o'clock in the morning a procession set forth from the Capitol tothe Pantheon, to render homage at the tomb of Raphael. It was arrangedin the following order: Two Fedeli, or municipal ushers, in picturesquecostumes of the sixteenth century, headed the procession, carrying twolaurel wreaths fastened with ribbons representing the colors of Rome, red and dark yellow; a company of Vigili, the Roman firemen; themunicipal band; the standard of Rome, carried by an officer of theVigili; and the banners of the fourteen quarters of the city. Then camethe Minister of Public Instruction and the Minister of Public Works; theSyndic of Rome, Duke Leopoldo Torlonia; and the Prefect of Rome, theMarquis Gravina. The members of the communal giunta, the provincialdeputation, and the communal and provincial council followed theprincipal authorities. Next in order came the presidents of Italian andforeign academies and art institutions, the president of the academy ofthe Licei, the representatives of all the foreign academies, the membersof the academy of St. Luke, the general direction of antiquities, themembers of the Permanent Commission of Fine Arts, the members of theCommunal Archæological Commission, the guardians of the Pantheon, themembers of the International Artistic Club, presided over by PrinceOdescalchi; the members of the art schools, the pupils of the SanMichele and Termini schools with their bands, the pupils of theelementary and female art schools. The procession was rendered moreinteresting by the presence of many Italian and foreign artists. Havingarrived at the Pantheon, the chief personages took their place in frontof Raphael's tomb. Every visitor to Rome knows this tomb, which issituated behind the third chapel on the left of the visitor entering thePantheon. The altar was endowed by Raphael, and behind it is a pictureof the Virgin and Child, known as the Madonna del Sasso, which wasexecuted at his request and was produced by Lorenzo Lotto, a friend andpupil of the great painter. Above the inscription usually hang a fewsmall pictures, which were presented by very poor artists who thoughtthemselves cured by prayers at the shrine. This is confirmed by a crutchhanging up close to the pilaster. The bones of Raphael are laid in thistomb since 1520, with an epitaph recording the esteem in which he washeld by Popes Julius II. And Leo X. ; but they have not always beenallowed to lie undisturbed. On Sept. 14, 1833, the tomb was opened toinspect the mouldering skeleton, of which drawings were made, and arereproduced in two of our illustrations. The proceedings at the tomb inthe recent anniversary visit were brief and simple; a number of laurelor floral wreaths were suspended there, one sent by the president andmembers of the Royal Academy of London; and the Syndic of Rome unveileda bronze bust of Raphael, which had been placed in a niche at the side. 

[Illustration: THE ANCIENT ROMAN TEMPLE NOW KNOWN AS THE PANTHEON, ATROME. ]

This ceremony at the Pantheon was concluded by all visitors writingtheir names on two albums which had been placed near Victor Emmanuel'stomb and Raphael's tomb. The commemoration in the hall of the Horatiiand Curiatii in the Capitol was a great success, their Majesties, theMinisters, the members of the diplomatic body, and a distinguishedassembly being present. Signor Quirino Leoni read an admirable discourseon Raphael and his times. 

The ancient city of Urbino, Raphael's birthplace, has fallen intodecay, but has remembered its historic renown upon this occasion. The representatives of the Government and municipal authorities, anddelegates of the leading Italian cities went in procession to visit thehouse where Raphael was born. Commemoration speeches were pronouncedin the great hall of the ducal palace by Signor Minghetti and SenatorMassarani. The commemoration ended with a cantata composed by SignorRossi. The Via Raffaelle was illuminated in the evening, and a galaspectacle was given at the Sanzio Theater. Next day the exhibition ofdesigns for a monument to Raphael was inaugurated at Urbino, and atnight a great torchlight procession took place. --_Illustrated LondonNews_. 

[Illustration: RAPHAEL'S TOMB IN THE PANTHEON, AT ROME. ]

 * * * * *

THE PANTHEON AT ROME. 

The edifice known as the Pantheon, in Rome, is one of the best preservedspecimens of Roman architecture. It was erected in the year 26 B. C. , and is therefore now about one thousand nine hundred years old. It wasconsecrated as a Christian church in the year 608. Its rotunda is 143ft. In diameter and also 143 ft. High. Its portico is remarkable for theelegance and number of its Corinthian columns. 

 * * * * *

Señor Felipe Poey, a famous ichthyologist of Cuba, has recently broughtout an exhaustive work upon the fishes of Cuban waters, in which hedescribes and depicts no fewer than 782 distinct varieties, although headmits some doubts about 105 kinds, concerning which he has yet to getmore exact information. There can be no question, however, he claims, about the 677 species remaining, more than half of which he firstdescribed in previous works upon this subject, which has been the studyof his life. 

 * * * * *

THE GREAT INTERNATIONAL FISHERIES EXHIBITION. 

Her Majesty the Queen has appointed the 12th of May for the openingof the International Fisheries Exhibition, which an influential andenergetic committee, under the active presidency of the Prince of Wales, had developed to a magnitude undreamt of by those concerned in its earlybeginnings. 

The idea of an _international_ Fisheries Exhibition arose out of thesuccess of the show of British fishery held at Norwich a short time ago;and the president and executive of the latter formed the nucleus of thefar more powerful body by whom the present enterprise has been broughtabout. 

The plan of the buildings embraces the whole of the twenty-two acres ofthe Horticultural Gardens; the upper half, left in its usual state ofcultivation, will form a pleasant lounge and resting place for visitorsin the intervals of their study of the collections. This element ofgarden accommodation was one of the most attractive features at theParis Exhibition of 1878. 

As the plan of the buildings is straggling and extended, and widelyseparates the classes, the most convenient mode of seeing the show willprobably be found by going through the surrounding buildings first, andthen taking the annexes as they occur. 

[Illustration: THE INTERNATIONAL FISHERIES EXHIBITION, LONDON. 

BLOCK PLAN. --A, Switzerland; B, Isle of Man; C, Bahamas and W. I. Islands; D, Hawaii; E, Poland; F, Portugal; G, Austria; H, Germany; I, France; J, Italy; K, Greece; L, China; M, India and Ceylon; N, StraitsSettlements; O, Japan; P, Tasmania; Q, New South Wales. --Scale 200 feetto the inch. ]

On entering the main doors in the Exhibition Road, we pass through theVestibule to the Council Room of the Royal Horticultural Society, which has been decorated for the reception of marine paintings, riversubjects, and fish pictures of all sorts, by modern artists. 

Leaving the Fine Arts behind, the principal building of the Exhibitionis before us--that devoted to the deep sea fisheries of Great Britain. It is a handsome wooden structure, 750 feet in length, 50 feet wide, and30 feet at its greatest height. The model of this, as well as of theother temporary wooden buildings, is the same as that of the annexes ofthe great Exhibition of 1862. 

On our left are the Dining Rooms with the kitchens in the rear. Thethird room, set apart for cheap fish dinners (one of the features of theExhibition), is to be decorated at the expense of the Baroness BurdettCoutts, and its walls are to be hung with pictures lent by theFishmongers' Company, who have also furnished the requisite chairs andtables, and have made arrangements for a daily supply of cheap fish, while almost everything necessary to its maintenance (forks, spoons, table-linen, etc. ) will be lent by various firms. 

The apsidal building attached is to be devoted to lectures on thecooking of fish. 

Having crossed the British Section, and turning to the right and passingby another entrance, we come upon what will be to all one of the mostinteresting features of the Exhibition, and to the scientific studentof ichthyology a collection of paramount importance. We allude to theWestern Arcade, in which are placed the Aquaria, which have in theirconstruction given rise to more thoughtful care and deliberation thanany other part of the works. On the right, in the bays, are the twentylarge asphalt tanks, about 12 feet long, 3 feet wide, and 3 feet deep. These are the largest dimensions that the space at command will allow, but it is feared by some that it will be found somewhat confined forfast going fish. Along the wall on the left are ranged twenty smaller ortable tanks of slate, which vary somewhat in size; the ten largest areabout 5 feet 8 inches long, 2 feet 9 inches wide, and 1 foot 9 inchesdeep. 

In this Western Arcade will be found all the new inventions in fishculture--models of hatching, breeding, and rearing establishments, apparatus for the transporting of fish, ova, models and drawings offish-passes and ladders, and representations of the development andgrowth of fish. The chief exhibitors are specialists, and are alreadywell known to our readers. Sir James Gibson Maitland has taken an activepart in the arrangement of this branch, and is himself one of theprincipal contributors. 

In the north of the Arcade, where it curves toward the Conservatory, will be shown an enormous collection of examples of stuffed fish, contributed by many prominent angling societies. In front of these onthe counter will be ranged microscopic preparations of parasites, etc. , and a stand from the Norwich Exhibition of a fauna of fish andfish-eating birds. 

Passing behind the Conservatory and down the Eastern Arcade--in whichwill be arranged algæ, sponges, mollusca, star-fish, worms used forbait, insects which destroy spawn or which serve as food for fish, etc. --on turning to the left, we find ourselves in the fish market, which will probably vie with the aquaria on the other side in attractingpopular attention. This model Billingsgate is to be divided into twoparts, the one for the sale of fresh, the other of dried and cured fish. 

Next in order come the two long iron sheds appropriated respectively tolife-boats and machinery in motion. Then past the Royal pavilion (theidea of which was doubtless taken from its prototype at the ParisExhibition) to the southern end of the central block, which is sharedby the Netherlands and Newfoundland; just to the north of the formerBelgium has a place. 

While the Committee of the Netherlands was one of the earliest formed, Belgium only came in at the eleventh hour; she will, however, owingto the zealous activity of Mr. Lenders, the consul in London, sendan important contribution worthy of her interest in the North Seafisheries. We ought also to mention that Newfoundland is among thosecolonies which have shown great energy, and she may be expected to senda large collection. 

Passing northward we come to Sweden and Norway, with Chili between them. These two countries were, like the Netherlands, early in preparing toparticipate in the Exhibition. Each has had its own committee, which hasbeen working hard since early in 1882. 

Parallel to the Scandinavian section is that devoted to Canada and theUnited States, and each will occupy an equal space--ten thousand squarefeet. 

In the northern Transept will be placed the inland fisheries of theUnited Kingdom. At each end of the building is aptly inclosed a basinformerly standing in the gardens: and over the eastern one will beerected the dais from which the Queen will formally declare theExhibition open. 

Shooting out at right angles are the Spanish annex, and the buildingshared by India and Ceylon. China and Japan and New South Wales; whilecorresponding to those at the western end are the Russian annex, and ashed allotted to several countries and colonies. The Isle of Man, theBahamas, Switzerland, Germany, Hawaii, Italy, and Greece--all find theirspace under its roof. 

After all the buildings were planned, the Governments of Russia andSpain declared their intention of participating; and accordingly foreach of these countries a commodious iron building has been speciallyerected. 

The Spanish collection will be of peculiar interest; it has beengathered together by a Government vessel ordered round the coast for thepurpose, and taking up contributions at all the seaports as it passed. 

Of the countries whose Governments for inscrutable reasons of state showdisfavor and lack of sympathy, Germany is prominent; although by theactive initiative of the London Committee some important contributionshave been secured from private individuals; among them, we are happy tosay, is Mr. Max von dem Borne, who will send his celebrated incubators, which the English Committee have arranged to exhibit in operation attheir own expense. 

Although the Italian Government, like that of Germany, holds aloof, individuals, especially Dr. Dohrn, of the Naples Zoological Station, will send contributions of great scientific value. 

In the Chinese and Japanese annex, on the east, will be seen a largecollection of specimens (including the gigantic crabs), which have beencollected, to great extent, at the suggestion of Dr. Günther, of theBritish Museum. 

It is at the same time fortunate and unfortunate that a similarFisheries Exhibition is now being held at Yokohama, as many specimenswhich have been collected specially for their own use would otherwise bewanting; and on the other hand, many are held back for their own show. 

China, of all foreign countries, was the first to send her goods, whicharrived at the building on the 30th of March, accompanied by nativeworkmen who are preparing to erect over a basin contiguous to theirannex models of the summer house and bridge with which the willowpattern plate has made us familiar; while on the basin will float modelsof Chinese junks. 

Of British colonies, New South Wales will contribute a very interestingcollection placed under the care of the Curator of the Sydney Museum;and from the Indian Empire will come a large gathering of specimens inspirits under the superintendence of Dr. Francis Day. 

Of great scientific interest are the exhibits, to be placed in twoneighboring sheds, of the Native Guano Company and the Millowners'Association. The former will show all the patents used for thepurification of the rivers from sewage, and the latter will display inaction their method of rendering innocuous the chemical pollutions whichfactories pour into the river. 

In the large piece of water in the northern part of the gardens, whichhas been deepened on purpose, apparatus in connection with diving willbe seen; and hard by, in a shed, Messrs. Siebe, Gorman & Co. Will showa selection of beautiful minute shells dredged from the bottom of theMediterranean. 

In the open basins in the gardens will be seen beavers, seals, sea-lions, waders, and other aquatic birds. 

From this preliminary walk round enough has, we think, been seen to showthat the Great International Fisheries Exhibition will prove of interestalike to the ordinary visitor, to those anxious for the well-beingof fishermen, to fishermen themselves of every degree, and to thescientific student of ichthyology in all its branches. --_Nature_. 

 * * * * *

PUPPET SHOWS AMONG THE GREEKS. 

The ancients, especially the Greeks, were very fond of theatricalrepresentations; but, as Mr. Magnin has remarked in his _Origines duThéâtre Moderne_, public representations were very expensive, and forthat very reason very rare. Moreover, those who were not in a conditionof freedom were excluded from them; and, finally, all cities could nothave a large theater, and provide for the expenses that it carried withit. It became necessary, then, for every day needs, for all conditionsand for all places, that there should be comedians of an inferior order, charged with the duty of offering continuously and inexpensively theemotions of the drama to all classes of inhabitants. 

Formerly, as to-day, there were seen wandering from village to villagemenageries, puppet shows, fortune tellers, jugglers, and performers oftricks of all kinds. These prestidigitators even obtained at times suchcelebrity that history has preserved their names for us--at least of twoof them, Euclides and Theodosius, to whom statues were erected by theircontemporaries. One of these was put up at Athens in the Theater ofBacchus, alongside of that of the great writer of tragedy, Æschylus, andthe other at the Theater of the Istiaians, holding in the hand a smallball. The grammarian Athenæus, who reports these facts in his "Banquetof the Sages, " profits by the occasion to deplore the taste of theAthenians, who preferred the inventions of mechanics to the culture ofmind and histrions to philosophers. He adds with vexation that Diophitesof Locris passed down to posterity simply because he came one day toThebes wearing around his body bladders filled with wine and milk, and so arranged that he could spurt at will one of these liquids inapparently drawing it from his mouth. What would Athenæus say if he knewthat it was through him alone that the name of this histrion had comedown to us?

[Illustration: FIG. 1. --THE MARVELOUS STATUE OF CYBELE. ]

Philo, of Byzantium, and Heron, of Alexandria, to whom we always haveto have recourse when we desire accurate information as to the mechanicarts of antiquity, both composed treatises on puppet shows. That ofPhilo is lost, but Heron's treatise has been preserved to us, and hasrecently been translated in part by Mr. Victor Prou. 

According to the Greek engineer, there were several kinds of puppetshows. The oldest and simplest consisted of a small stationary case, isolated on every side, in which the stage was closed by doors thatopened automatically several times to exhibit the different tableaux. The programme of the representation was generally as follows: The firsttableau showed a head, painted on the back of the stage, which movedits eyes, and lowered and raised them alternately. The door having beenclosed, and then opened again, there was seen, instead of the head, agroup of persons. Finally, the stage opened a third time to show a newgroup, and this finished the representation. There were, then, onlythree movements to be made, that of the doors, that of the eyes, andthat of the change of background. 

As such representations were often given on the stages of largetheaters, a method was devised later on of causing the case to startfrom the scenes behind which it was bidden from the spectators, and ofmoving automatically to the front of the stage, where it exhibited insuccession the different tableaux; after which it returned automaticallybehind the scenes. Here is one of the scenes indicated by Heron, entitled the "Triumph of Bacchus":

The movable case shows, at its upper part, a platform from which arisesa cylindrical temple, the roof of which, supported by six columns, isconical and surmounted by a figure of Victory with spread wings andholding a crown in her right hand. In the center of the temple Bacchusis seen standing, holding a thyrsus in his left hand, and a cup in hisright. At his feet lies a panther. In front of and behind the god, onthe platform of the stage, are two altars provided with combustiblematerial. Very near the columns, but external to them, there arebacchantes placed in any posture that may be desired. All being thusprepared, says Heron, the automatic apparatus is set in motion. Thetheater then moves of itself to the spot selected, and there stops. Thenthe altar in front of Jupiter becomes lighted, and, at the same time, milk and water spurt from his thyrsus, while his cup pours wine over thepanther. The four faces of the base become encircled with crowns, and, to the noise of drums and cymbals, the bacchantes dance round about thetemple. Soon, the noise having ceased, Victory on the top of the temple, and Bacchus within it, face about. The altar that was behind the godis now in front of him, and becomes lighted in its turn. Then occursanother outflow from the thyrsus and cup, and another round of thebacchantes to the sound of drums and cymbals. The dance being finished, the theater returns to its former station. Thus ends the apotheosis. 

I shall try to briefly indicate the processes which permitted of thesedifferent operations being performed, and which offer a much moregeneral interest than one might at first sight be led to believe; foralmost all of them had been employed in former times for producing theillusions to which ancient religions owed their power. 

The automatic movement of the case was obtained by means ofcounterpoises and two cords wound about horizontal bobbins in such a wayas to produce by their winding up a forward motion in a vertical plane, and subsequently a backward movement to the starting place. Supposingthe motive cords properly wound around vertical bobbins, instead of ahorizontal one, and we have the half revolution of Bacchus and Victory, as well as the complete revolution of the bacchantes. 

The successive lighting of the two altars, the flow of milk and wine, and the noise of drums and cymbals were likewise obtained by the aid ofcords moved by counterpoises, and the lengths of which were graduatedin such a way as to open and close orifices, at the proper moment, byacting through traction on sliding valves which kept them closed. 

Small pieces of combustible material were piled up beforehand on the twoaltars, the bodies of which were of metal, and in the interior of whichwere hidden small lamps that were separated from the combustible by ametal plate which was drawn aside at the proper moment by a smallchain. The flame, on traversing the orifice, thus communicated with thecombustible. 

The milk and wine which flowed out at two different times through thethyrsus and cup of Bacchus came from a double reservoir hidden under theroof of the temple, over the orifices. The latter communicated, each ofthem, with one of the halves of the reservoir through two tubes insertedin the columns of the small edifice. These tubes were prolonged underthe floor of the stage, and extended upward to the hands of Bacchus. Akey, maneuvered by cords, alternately opened and closed the orificeswhich gave passage to the two liquids. 

As for the noise of the drums and cymbals, that resulted from thefalling of granules of lead, contained in an invisible box provided withan automatic sliding-valve, upon an inclined tambourine, whence theyrebounded against little cymbals in the interior of the base of the car. 

[Illustration: FIG. 2. --MARVELOUS ALTAR (According to Heron). ]

Finally, the crowns and garlands that suddenly made their appearance onthe four faces of the base of the stage were hidden there in advancebetween the two walls surrounding the base. The space thus made for thecrowns was closed beneath, along each face, by a horizontal trap movingon hinges that connected it with the inner wall of the base, but whichwas held temporarily stationary by means of a catch. The crowns wereattached to the top of their compartment by cords that would haveallowed them to fall to the level of the pedestal, had they not beensupported by the traps. 

At the desired moment, the catch, which was controlled by a specialcord, ceased to hold the trap, and the latter, falling vertically, gavepassage to the festoons and crowns that small leaden weights then drewalong with all the quickness necessary. 

Two points here are specially worthy of attracting our attention, andthese are the flow of wine or milk from the statue of Bacchus, andthe spontaneous lighting of the altar. These, in fact, were the twoillusions that were most admired in ancient times, and there wereseveral processes of performing them. Father Kircher possessed in hismuseum an apparatus which he describes in _Oedipus Egyptiacus_ (t. Ii. , p. 333), and which probably came from some ancient Egyptian temple. (Fig. 1. )

It consisted of a hollow hemispherical dome, supported by four columns, and placed over the statue of the goddess of many breasts. To two ofthese columns were adapted movable brackets, at whose extremities therewere fixed lamps. The hemisphere was hermetically closed underneath by ametal plate. The small altar which supported the statue, and which wasfilled with milk, communicated with the interior of the statue by a tubereaching nearly to the bottom. The altar likewise communicated withthe hollow dome by a tube having a double bend. At the moment of thesacrifice the two lamps were lighted and the brackets turned so that theflames should come in contact with and heat the bottom of the dome. Theair contained in the latter, being dilated, issued through the tube, XM, pressed on the milk contained in the altar, and caused it to risethrough the straight tube into the interior of the statue as high asthe breasts. A series of small conduits, into which the principal tubedivided, carried the liquid to the breasts, whence it spurted out, tothe great admiration of the spectators, who cried out at the miracle. The sacrifice being ended, the lamps were put out, and the milk ceasedto flow. 

Heron, of Alexandria, describes in his _Pneumatics_ several analogousapparatus. Here is one of them. (We translate the Greek text literally. )

[Illustration: Fig. 3. --MARVELOUS ALTAR (According to Heron). ]

"To construct an altar in such a way that, when a fire is lightedthereon, the statues at the side of it shall make libations. (Fig. 2. )

"Let there be a pedestal. A B [Gamma] [Delta], on which are placedstatues, and an altar, E Z H, closed on every side. The pedestal shouldalso be hermetically closed, but is communicated with the altar througha central tube. It is traversed likewise by the tube, e [Lambda] (inthe interior of the statue to the right), not far from the bottom whichterminates in a cup held by the statue, e. Water is poured into thepedestal through a hole, M, which is afterward corked up. 

"If, then, a fire be lighted on the altar, the internal air will bedilated and will enter the pedestal and drive out the water contained init. But the latter, having no other exit than the tube, e [Lambda], willrise into the cup, and so the statue will make a libation. This willlast as long as the fire does. On extinguishing the fire the libationceases, and occurs anew as often as the fire is relighted. 

"It is necessary that the tube through which the heat is to introduceitself shall be wider in the middle; and it is necessary, in fact, thatthe heat, or rather that the draught that it produces, shall accumulatein an inflation in order to have more effect. "

According to Father Kircher (_l. C. _), an author whom he calls Bithoreports that there was at Sais a temple of Minerva in which there was analtar on which, when a fire was lighted, Dyonysos and Artemis (Bacchusand Diana) poured milk and wine, while a dragon hissed. 

It is easy to conceive of the modification to be introduced into theapparatus above described by Heron, in order to cause the outflow ofmilk from one side and of wine from the other. 

After having indicated it, Father Kircher adds: "It is thus that Bacchusand Diana appeared to pour, one of them wine, and the other milk, andthat the dragon seemed to applaud their action by hisses. As the peoplewho were present at the spectacle did not see what was going on within, it is not astonishing that they believed it due to divine intervention. We know, in fact, that Osiris or Bacchus was considered as thediscoverer of the vine and of milk; that Iris was the genius of thewaters of the Nile; and that the Serpent, or good genius, was the firstcause of all these things. Since, moreover, sacrifices had to be made tothe gods in order to obtain benefits, the flow of milk, wine, or water, as well as the hissing of the serpent, when the sacrificial flame waslighted, appeared to demonstrate clearly the existence of the gods. "

In another analogous apparatus of Heron's, it is steam that performs therole that we have just seen played by dilated air. But the ancients donot appear to have perceived the essential difference, as regards motivepower, that exists between these two agents; indeed, their preferenceswere wholly for air, although the effects produced were not very great. We might cite several small machines of this sort, but we shall confineourselves to one example that has some relation to our subject. Thisalso is borrowed from Heron's _Pneumatics_. (Fig. 3. )

"Fire being lighted on an altar, figures will appear to execute a rounddance. The altars should be transparent, and of glass or horn. From thefire-place there starts a tube which runs to the base of the altar, where it revolves on a pivot, while its upper part revolves in a tubefixed to the fire-place. To the tube there should be adjusted othertubes (horizontal) in communication with it, which cross each otherat right angles, and which are bent in opposite directions at theirextremities. There is likewise fixed to it a disk upon which areattached figures which form a round. When the fire of the altar islighted, the air, becoming heated, will pass into the tube; but beingdriven from the latter, it will pass through the small bent tubes and... Cause the tube as well as the figures to revolve. "

Father Kircher, who had at his disposal either many documents that weare not acquainted with, or else a very lively imagination, alleges(_Oedip. Æg. _, t. Ii. , p. 338) that King Menes took much delight inseeing such figures revolve. 

Nor are the examples of holy fire-places that kindled spontaneouslywanting in antiquity. 

Pliny (_Hist. Nat_. , ii. , 7) and Horace (_Serm. , Sat. V. _) tell us thatthis phenomenon occurred in the temple of Gnatia, and Solin (Ch. V. )says that it was observed likewise on an altar near Agrigentum. Athenæus (_Deipn_. I. , 15) says that the celebrated prestidigitator, Cratisthenes, of Phlius, pupil of another celebrated prestidigitatornamed Xenophon, knew the art of preparing a fire which lightedspontaneously. 

Pausanias tells us that in a city of Lydia, whose inhabitants, havingfallen under the yoke of the Persians, had embraced the religion of theMagi, "there exists an altar upon which there are ashes which, in color, resemble no other. The priest puts wood on the altar, and invokes Iknow not what god by harangues taken from a book written in a barbaroustongue unknown to the Greeks, when the wood soon lights of itselfwithout fire, and the flame from it is very clear. "

The secret, or rather one of the secrets of the Magi, has been revealedto us by one of the Fathers of the Church (Saint Hippolytus, it isthought), who has left, in a work entitled _Philosophumena_, whichis designed to refute the doctrines of the pagans, a chapter on theillusions of their priests. According to him, the altars on which thismiracle took place contained, instead of ashes, calcined lime and alarge quantity of incense reduced to powder; and this would explain theunusual color of the ashes observed by Pausanias. The process, moreover, is excellent; for it is only necessary to throw a little water on thelime, with certain precautions, to develop a heat capable of setting onfire incense or any other material that is more readily combustible, such as sulphur and phosphorus. The same author points out still anothermeans, and this consists in hiding firebrands in small bells that wereafterward covered with shavings, the latter having previously beencovered with a composition made of naphtha and bitumen (Greek fire). As may be seen, a very small movement sufficed to bring aboutcombustion. --_A. De Rochas, in La Nature_. 

 * * * * *

TORPEDO BOATS. 

There are several kinds of torpedoes. The one which is most used in theFrench navy is called the "carried" torpedo (_torpille portée_), thusnamed because the torpedo boat literally _carries_ it right under thesides of the enemy's ship. It consists of a cartridge of about 20kilogrammes of gun cotton, placed at the extremity of an iron rod, 12meters in length, projecting in a downward direction from the fore partof the boat. The charge is fired by an electric spark by means of anapparatus placed in the lookout compartment. Our engraving represents anattack on an ironclad by means of one of these torpedoes. Under cover ofdarkness, the torpedo boat has been enabled to approach without beingdisabled by the projectiles from the revolving guns of the man-of-war, and has stopped suddenly and ignited the torpedo as soon as the lattercame in contact with the enemy's hull. 

The water spout produced by the explosion sometimes completely coversthe torpedo boat, and the latter would be sunk by it were notall apertures closed so as to make her a true buoy. What appearsextraordinary is that the explosion does not prove as dangerous to theassailant as to the adversary. To understand this it must be rememberedthat, although the material with which the cartridges are filled is ofan extreme _shattering_ nature, and makes a breach in the most resistantarmor plate, when in _contact_ with it, yet, at a distance of a fewmeters, no other effect is felt from it than the disturbance caused bythe water. This is why a space of 12 meters, represented by the lengthof the torpedo spar, is sufficient to protect the torpedo boat. Theattack of an ironclad, however, under the conditions that we have justdescribed, is, nevertheless, a perilous operation, and one that requiresmen of coolness, courage, and great experience. 

[Illustration: ATTACK BY A TORPEDO BOAT UPON AN IRON CLAD SHIP OF WAR. ]

There is another system which is likewise in use in the French navy, andthat is the Whitehead torpedo. This consists of a metallic cylinder, tapering at each end, and containing not only a charge of gun cotton, but a compressed air engine which actuates two helices. It is, in fact, a small submarine vessel, which moves of itself in the direction towardwhich it has been launched, and at a depth that has been regulatedbeforehand by a special apparatus which is a secret with the inventor. The torpedo is placed in a tube situated in the fore part of the torpedoboat, and whence it is driven out by means of compressed air. Oncefired, it makes its way under the surface to the spot where the shock ofits point is to bring about an explosion, and the torpedo boat is thusenabled to operate at a distance and avoid the dangers of an immediatecontact with the enemy. Unfortunately this advantage is offset by gravedrawbacks; for, in the first place, each of the Whitehead torpedoescosts about ten thousand francs, without counting the expense ofobtaining the right to use the patent, and, in the second place, itsaction is very uncertain, since currents very readily change itsdirection. However this may be, the inventor has realized a considerablesum by the sale of his secret to the different maritime powers, most ofwhom have adopted his system. 

All our ports are provided with flotillas and torpedo boats, and withschools in which the officers and men charged with this service aretrained by frequent exercises. It was near L'Orient, at Port Louis, thatwe were permitted to be witnesses of these maneuvers, and where we sawthe torpedo boats that were lying in ambush behind Rohellan Isle glidebetween the rocks, all of which appeared familiar to them, and start outseaward at the first signal. It was here, too, that we were witnessesof the sham attack against a pleasure yacht, shown in one of ourengravings. A torpedo boat, driven at full speed, stopped at one meterfrom the said yacht with a precision that denoted an oft-repeated study. 

[Illustration: MODE OF FIRING TORPEDOES. ]

Before we close, we must mention some very recent experiments that havebeen made with a torpedo analogous to Whitehead's, that is to say, onethat runs alone by means of helices actuated by compressed air, buthaving the great advantage that it can be steered at a distance from thevery place whence it has been launched. This extraordinary result isobtained by the use of a rudder actuated by an electric current which istransmitted by a small metallic cable wound up in the interior of thetorpedo, and paying out behind as the torpedo moves forward on itsmission. The operator, stationed at the starting point, is obliged tofollow the torpedo's course with his eyes in order to direct it duringits submarine voyage. For this reason the torpedo carries a verticalmast, that projects above the surface, and at the top of which is placeda lantern, whose light is thrown astern but is invisible from the front, that is, from the direction of the enemy. A trial of this ingeniousinvention was made a few weeks ago on the Bosphorus, with completesuccess, as it appears. From the shore where the torpedo was put intothe water, the weapon was steered with sufficient accuracy to cause itto pass, at a distance of two kilometers, between two vessels placed inobservation at a distance apart of ten meters. After this, it was madeto turn about so as to come back to its starting point. What makes thisresult the more remarkable is that the waters of the Bosphorus aredisturbed by powerful currents that run in different directions, according to the place. --_L'Illustration_. 

 * * * * *

PICTET'S HIGH SPEED BOAT. 

It is now nearly a year ago since we announced to our readers theresearches that had been undertaken by the learned physicist, RaoulPictet, in order to demonstrate theoretically and practically the formsthat are required for a fast-sailing vessel, and since we pointed outhow great an interest is connected with the question, while at the sametime promising to revert to the subject at some opportune moment. Weshall now keep our promise by making known a work that Mr. Pictet hasjust published in the _Archives Physiques et Naturelles_, of Geneva, in which he gives the first results of his labors, and which we shallanalyze rapidly, neglecting in doing so the somewhat dry mathematicalpart of the article. 

For a given tonnage and identical tractive stresses, the greater or lesssharpness of the fore and aft part of the keel allows boats to attaindifferent speeds, the sharper lines corresponding to the highest speeds, but, in practice, considerably diminishing the weight of freight capableof being carried by the boat. 

[Illustration: FIG. 1. PICTET'S HIGH SPEED BOAT. 

A. Lateral View. B. Plan. C. Section of the boiler room. D. Section ofthe cabin. ]

Mr. Pictet proposed the problem to himself in a different manner, and asfollows:

Determine by analysis, and verify experimentally, what form of keel willallow of the quickest and most economical carriage of a given weight ofmerchandise on water. 

We know that for a given transverse or midship section, the tractivestress necessary for the progression of the ship is proportional to the_square_ of the velocity; and the motive power, as a consequence, to the_cube_ of such velocity. 

[Illustration: Fig. 2. --Diagram of tractive stresses at differentspeeds. ]

The _friction_ of water against the polished surfaces of the vessel'ssides has not as yet been directly measured, but some indirectexperiments permit us to consider the resistances due thereto as small. The entire power expended for the progress of the vessel is, then, utilized solely in displacing certain masses of water and in giving thema certain amount of acceleration. The masses of water set in motiondepend upon the surface submerged, and their acceleration depends uponthe speed of the vessel. Mr. Pictet has studied a form of vessel inwhich the greatest part possible of the masses of water set in motionshall be given a vertical acceleration, and the smallest part possiblea horizontal one; and this is the reason why: All those masses of waterwhich shall receive a vertical acceleration from the keel will tend tomove downward and produce a vertical reaction in an upward directionapplied to the very surface that gives rise to the motion. Such reactionwill have the effect of changing the level of the floating body; oflifting it while relieving it of a weight exactly equal to the valueof the vertical thrust; and of diminishing the midship section, and, consequently, the motive power. 

[Illustration: Fig. 3. --Diagram of variations in tractive stresses andtonnage taken as a function of the speed. ]

All those masses of water which receive a horizontal acceleration fromthe keel run counter, on the contrary, to the propulsive stress, and itbecomes of interest, therefore, to bring them to a minimum. The verticalstress is limited by the weight of the boat, and, theoretically, with aninfinite degree of speed, the boat would graze the water without beingable to enter it. 

The annexed diagram (Fig. 1) shows the form that calculation has led Mr. Pictet to. The sides of the boat are two planes parallel with its axis, and perfectly vertical. The keel (properly so called) is formed bythe joining of the two vertical planes. The surface thus formed is aparabola whose apex is in front, the maximum ordinate behind, and theconcavity directed toward the bottom of the water. The stern is avertical plane intersecting at right angles the two lateral faces andthe parabolic curve, which thus terminates in a sharp edge. The prow ofthe boat is connected with the apex of the parabola by a curve whoseconcavity is directed upward. 

[Illustration: Fig. 4. --Diagram of the variations in the power as afunction of the speed. ]

When we trace the curve of the tractive stresses in a boat thusconstructed, by putting the speeds in abscisses and the tractivestresses in ordinates, we obtain a curve (Fig. 2) which shows that thesame tractive stress applied to a boat may give it three differentspeeds, M, M', and M'', only two of which, M and M'', are stable. 

Experimental verifications of this study have been partially realized(thanks to the financial aid of a number of persons who are interestedin the question) through the construction of a boat (Fig. 1) by theGeneva Society for the Construction of Physical Instruments. The vesselis 20. 25 m. In length at the water line, has an everywhere equal widthof 3. 9 m. , and a length of 16 m. From the stern to the apex of theparabola of the keel. The bottom of the boat is nearly absolutely flat. The keel, which is 30 centimeters in width, contains the shaft of thescrew. The boiler, which is designed for running at twelve atmospheres, furnishes steam to a two cylinder engine, which may be run at will, either the two cylinders separately, or as a _compound_ engine. Thebronze screw is 1. 3 m. In diameter, and has a pitch of 2. 5 m. The vesselhas two rudders, one in front for slight speeds, and the other at thestern. At rest, the total displacement is 52, 300 kilogrammes. This weight far exceeds what was first expected, by reason of thesuperthickness given the iron plates of the vertical sides, of thesupplementary cross bracing, and of the superposition of the nettingnecessary to resist the flexion of the whole. On another hand, the tractive stress of the screw, which should reach about 4, 000kilogrammes, has never been able to exceed 1, 800, because of thenumerous imperfections in the engine. It became necessary, therefore, to steady the vessel by having her towed by the _Winkelried_, which waschartered for such a purpose, to the General Navigation Company. Itbecame possible to thus carry on observations on speeds up to 27kilometers per hour. 

Fig. 3 shows how the tractive stress varies with each speed in atheoretic case (dotted curve) in which the stress is proportional to thesquare of the speed, in Madame Rothschild's boat, the _Gitana_ (curveE), and in the Pictet high speed vessel (curve B). 

The _Gitana_ was tried with speeds varying between 0 and 4 kilometers. The corresponding tractive stresses have been reduced to the sametransverse section as in the Pictet model in order to render theobservations comparable. At slight speeds, and up to 19. 5 kilometers perhour, the _Gitana_, which is the sharper, runs easier and requires aslighter tractive stress. At such a speed there is an equality; but, beyond this, the Pictet boat presents the greater advantages, and, at aspeed of 27 kilometers, requires a stress about half less than does the_Gitana_. Such results explain themselves when we reflect that at thesegreat speeds the _Gitana_ sinks to such a degree that the aftersideplanks are at the level of the water, while the Pictet model risessimultaneously fore and aft, thus considerably diminishing the submergedsection. 

With low or moderate speeds there is a perceptible equality between thetheoretic curve and the curve of the fast boat; but, starting from 16kilometers, the stress diminishes. The greater does the speed become, the more considerable is the diminution in stress; and, starting from acertain speed, the rise of the boat is such as to diminish its absolutetractive stress--a fact of prime importance established by theory andconfirmed by experiment. 

The curves in Fig. 4 show the power in horses necessary to effectprogression at different speeds. The curve, A, has reference to anordinary boat that preserves its water lines constant, and the curve, B, to a swift boat of the same tonnage. Up to 16 kilometers, the swiftvessel presents no advantage; but beyond that speed, the advantagebecomes marked, and, at a speed of 27 kilometers, the power to beexpended is no more than half that which corresponds to the same speedfor an ordinary boat. 

The water escapes in a thin and even sheet as soon as the tractivestress exceeds 2, 000 kilogrammes; and the intensity and size ofthe eddies from the boat sensibly diminish in measure as the speedincreases. 

The interesting experiments made by Mr. Pictet seem, then to clearlyestablish the fact that the forms deduced by calculation are favorableto high speeds, and will permit of realizing, in the future, importantsaving in the power expended, and, consequently, in the fuel (much lessof which will need to be carried), in order to perform a given passagewithin a given length of time. Thus is explained the great interest thatattaches to Mr. Pictet's labors, and the desire that we have to soon beable to make known the results obtained with such great speeds, not whenthe boat is towed, but when its propulsion is effected through itsown helix actuated by its own engine, which, up to the present, unfortunately, has through its defects been powerless to furnish thenecessary amount of power for the purpose. --_La Nature_. 

 * * * * *

INITIAL STABILITY INDICATOR FOR SHIPS. 

For a vessel with a given displacement, the metacenter and center ofgravity being known, it is easy to lay off in the form of a diagramits stability or power of righting for any given angle of heel. Such adiagram is shown in Fig. 3, in which the abscissæ are the angles of theheel, and the ordinates the various lengths of the levers, at the endof which the whole weight of the vessel is acting to right itself. The curve may be constructed in the following manner: Having found bycalculation the position of the transverse metacenter, M, for a givendisplacement--Figs. 1 and 2--the metacentric height, G M, is thendetermined either by calculations, or more correctly by experiment, byvarying the position of weights of known magnitude, or by the stabilityindicator itself. Suppose, now, the vessel to be listed over to variousangles of heel--say 20 deg. , 40 deg. , 60 deg. , and 80 deg. --the waterlines will then be A C, D E, F K, and H J respectively, and the centersof buoyancy, which must be found by calculation, will be B1, B2, B3, andB4. If lines are drawn from these points at right angles to the waterlevels at the respective heels, the righting power of the vessel in eachposition is found by taking the perpendicular distances between theselines and the center of gravity, G. This method of construction is shownto an enlarged scale in Fig. 2, where G is the center of gravity, B1Z1, B2 Z2, B3 Z3, and B4 Z4 the lines from centers of buoyancy to waterlevels; and G N, G O, and G P the distances showing the righting powerat the angles of 20 deg. , 40 deg. , and 60 deg. Respectively, and whichto any convenient scale are set off as the ordinates in the stabilitycurve shown in Fig 3. 

[Illustration: STABILITY INDICATOR FOR SHIPS. Fig. 1. ]

Having obtained the curve, A, in this manner for a given metacentricheight, we will suppose that on the next voyage, with the samedisplacement, it is found that, owing to some difference in stowage, the center of gravity is 6 in. Higher than before. The ordinates of thecurve will then be G¹ N¹ and G¹ O¹--Fig. 2--and the stability curve willbe as at C--Fig. 3--showing that at about 47 deg. All righting powerceases. Similarly, if the center of gravity is lowered 6 in. On thesame displacement, the curve, B, will be found, and in this mannercomparative diagrams can be constructed giving at a glance the stabilityof a vessel for any given draught of water and metacentric height. 

[Illustration: STABILITY INDICATOR FOR SHIPS. Fig. 2. ]

[Illustration: STABILITY INDICATOR FOR SHIPS. Fig. 3. ]

The object of Mr. Alexander Taylor's indicator is to measure and showby simple inspection the metacentric height under every condition ofloading, and therefore to make known the stability of the vessel. Itconsists of a small reservoir, A, Fig. 4, placed at one side of theship, in the cabin, or other convenient locality, communicating by atube with the glass gauge, B, secured at the opposite side, the wholebeing half filled with glycerine, which is the fluid recommended by Mr. Wm. Denny, though water or any other liquid will answer the purpose. At one side of the gauge is the circular scale, C, capable of beingrevolved round its vertical axis, as well as adjusted up and down, soas to bring the zero pointer exactly to the top of the fluid when thevessel is without list. Round the top of the scale, at D, are engravedfour different draughts, and under these are the metacentric heights. Test tanks of known capacity are placed at each side of the vessel, butin no way connected with the reservoir or gauge. The metacentric heightis found as follows: The ship being freed from bilge water, the rollerscale is turned round to bring to the front the mark corresponding withthe mean draught of the vessel at the time, and the zero pointer isplaced opposite the surface of the liquid in the gauge. One of the testtanks being filled with a known weight of water, the vessel is causedto list, and in consequence the liquid in the tube takes a new positioncorresponding with the degree of heel, the disturbance being greateraccording as the vessel has been more or less overbalanced. The scalehaving previously been properly graduated, the metacentric height forthe draught and state of loading can be at once read off in inches, while as a check the water can be transferred from the one test tank tothe other, and the metacentric height read off as before, but on theopposite side of the zero pointer. At the same time the angle of heel isshown on a second graduated scale, E. Having obtained the metacentricheight, reference to a diagram will at once show the whole range ofstability; and this being ascertained at each loading, the stowage ofthe cargo can be so adjusted as to avoid excessive stiffness in the onehand and dangerous tenderness on the other. It will thus be seen thatMr. Taylor's invention promises to be of great practical value both inthe hands of the ship-builder and ship-owner, who have now an instrumentplaced before them, by the proper use of which all danger fromunskillful loading can be entirely avoided. --_The Engineer_. 

[Illustration: STABILITY INDICATOR FOR SHIPS. Fig. 4. ]

 * * * * *

SCRIVANOW'S CHLORIDE OF SILVER PILE. 

Considerable attention has been attracted lately at Paris among thosewho are interested in electrical novelties to a chloride of silverpile invented by Mr. Scrivanow. The experiments to which it has beensubmitted are, in some respects, sufficiently extraordinary to cause usto make them known to our readers, along with the inventor's descriptionof the apparatus. 

Mr. Scrivanow's intention appears to be to apply this pile to thelighting of apartments, and even to the running of small motors, and, for the purpose of actuating sewing machines, he has already constructeda small model whose external dimensions are 160 x 100 x 90 millimeters. 

"My invention, " says the inventor, "is intended as an electric pilecapable of regeneration. The annexed Fig. 1 shows a vertical arrangementof the apparatus, and Fig. 2 a horizontal one. In the latter, twoelements are represented superposed. 

"My pile consists of a prism of retort carbon (a) covered on every sidewith pure chloride of silver (b). The carbon thus prepared is immersedin a solution of hydrate of potassium (KHO) or of hydrate of sodium(NaHO), marking 1. 30 to 1. 45 by the Baumé areometer, the solvent beingwater. 

"In the vicinity of the carbon is arranged the plate to be attacked--aplate of zinc (c) of good quality. The surface of the electrodes, andtheir distance apart, depends upon the effects that it is desired toobtain, and is determined in accordance with the well known principlesof electro-kinetics. 

"The chemical reactions that take place in this couple are multiple. In contact with a sufficiently concentrated solution of hydrate ofpotassium or sodium, the chloride of silver, especially if it has beenrecently prepared, passes partially into the state of brown or blackoxide, so that the carbon becomes covered, after remaining sufficientlylong in the exciting liquid, with a mixture of chloride and oxide ofsilver. When the circuit is closed, the chloride becomes reduced to aspongy metallic state and adheres to the surface of the carbon. At thesame time the zinc passes, in the alkaline solution, into a state ofchloride and of soluble combination of zinc oxide and of alkali. 

"To avoid all loss of silver I cover the carbon with asbestos paper, orwith cloth of the same material, d. My piles are arranged in ebonitevessels, A, which are flat, as in Fig. 1, or round, as in Fig. 2. 

"In Fig 1 there is seen, at e, gutta-percha separating the zinc from thecarbon at the base. 

"Under such conditions, we obtain a powerful couple that possesses anelectro-motive power of 1. 5 to 1. 8 volts, according to the concentrationof the exciting liquid. The internal resistance is extremely feeble. Ihave obtained with piles arranged like those shown in the figures nearly0. 06 ohm, the measurements having been taken from a newly charged pile. 

"When the element is used up, and, notably, when all the chloride ofsilver is reduced, it is only necessary to plunge the carbon with itsasbestos covering (after washing it in water) into a chloridizing bath, in order to bring back the metallic silver that invests the carbon to astate of chloride, and thus restore the pile to its primitive energy. After this the carbon is washed and put back into the exciting liquid. 

"These reductions of the chloride of silver during the operation of thepile can be reproduced _ad infinitum_, since they are accompanied by noloss of metal. The alkaline liquid is sufficient in quantity for twosuccessive charges of the couple. 

"The chloridizing bath consists of 100 parts of acetic acid, 5 to 6parts, by weight, of hydrochloric acid, and about 30 parts of water. 

[Illustration: FIG. 1. --SCRIVANOW'S CHLORIDE OF SILVER PILE. ]

"Other acids may be employed equally as well. A bath composed ofchlorochromate of potassium and nitric or sulphuric acid makes anexcellent regenerator. 

"To sum up, I claim as the distinctive characters of my pile:

"1. The use of the potassic or sodic alkaline liquid conjointly withchloride of silver, and the oxide of the same, that forms through theimmersion of the carbon in a chloridizing bath. 

"2. The use of retort or other carbon covered with the salt of silverabove specified. 

"3. The arrangement and construction of my pile as I have described. "

In the experiments recently tried with Mr. Scrivanow's pile, a largesized battery was made use of, whose dimensions were 300 x 145 x 125millimeters, and whose weight was from 5 to 6 kilogrammes. The resultswere: intensity, 1 ampere; electro-motive power, 25 volts, correspondingto an energy of 25 volt-amperes, or about 2. 5 kilogrammeters per second. The pile was covered with a copper jacket whose upper parts supportedtwo Swan lamps. Upon putting on the cover a contact was formed with theelectrodes, and it was possible by means of a commutator key with threeeccentrics to light or extinguish one of the lamps or both at once. A single element would have sufficed to keep one Swan lamp of feebleresistance lighted for 20 hours. Accepting the data given above andthe 20 hours' uninterrupted duration of the pile's operation the powerfurnished by this large model is equal to 2. 5 x 20 x 3, 600 = 180, 000kilogrammeters. 

[Illustration: FIG. 1. --SCRIVANOW'S CHLORIDE OF SILVER PILE. ]

In our opinion, Mr. Scrivanow's pile is not adapted for industrial usebecause of the expense of the silver and the frequent manipulations itrequires, but it has the advantage, however, of possessing, along withits small size and little weight, a disposable energy of from 150, 000to 200, 000 kilogrammeters utilizable at the will of the consumer andsecuring to him a certain number of applications, either for lighting orthe production of power. It appears to us to be specially destined tobecome a rival to the bichromate of potash pile for actuating electricmotors applied to the directing of balloons. --_Revue Industrielle_. 

 * * * * *

ON THE LUMINOSITY OF FLAME. 

The light emitted from burning gases which burn with bright flame isknown to be a secondary phenomenon. It is the solid, or even liquid, constituents separated out by the high temperature of combustion, andrendered incandescent, that emit the light rays. Gases, on the otherhand, which produce no glowing solid or liquid particles duringcombustion burn throughout with a weakly luminous flame of bluish orother color, according to the kind of gas. Now, it is common to say, merely, in explanation of this luminosity, that the gas highly heated incombustion is self-incandescent. This explanation, however, has not beenexperimentally confirmed. Dr Werner Siemens was, therefore, led recentlyto investigate whether highly-heated pure gases really emit light. 

The temperature employed in such experiments should, to be decisive, be higher than those produced by luminous combustion. The author hadrecourse to the regenerative furnace used by his brother, Friedrich, inDresden, in manufacture of hard glass. This stands in a separate roomwhich at night can be made perfectly dark. The furnace has, in themiddle of its longer sides, two opposite apertures, allowing free visionthrough. It can be easily heated to the melting temperature of steel, which is between 1, 500° and 2, 000° C. Before the furnace apertures wereplaced a series of smoke blackened screens with central openings, whichenabled one to look through without receiving, on the eye, rays from thefurnace walls. If, now, all air exchange was prevented in the furnace, and all light excluded from the room, it was found that not the leastlight came to the eye from the highly-heated air in the furnace. Forsuccess of the experiment, it was necessary to avoid any combustion inthe furnace, and to wait until the furnace-air was as free from dust aspossible. Any flame in the furnace (even when it did not reach into theline of sight), and the least quantity of dust in it, illuminated thefield of vision. 

As a result of these experiments, Dr. Siemens considers that the viewhitherto held, that highly-heated gases are self-luminous, is notcorrect. In the furnace were the products of the previous combustionand atmospheric air: consequently oxygen, nitrogen, carbonic acid, andaqueous vapor. If even one of these gases was self-luminous, the fieldof vision must have been always illuminated. The weak light given bythe flame of burning gases that separate out no solid nor liquidconstituents cannot, therefore, be explained as a phenomenon of glow ofthe gaseous products. 

It appealed to the author probable, that heated gases did not, either, emit heat rays; and he set himself to test this idea, experimenting, incompany with Herr Fröhlich, in Dresden. They first convinced themselvesin this case that the light emission of pure heated gases sunk to zero, even when the field of vision was not always quite dark, and it wasonly possible to observe this a short time; but the repeatedly observedperfect darkness of the field of vision was demonstrative. On the otherhand, experiments made with sensitive thermopiles, in order to settlethe question of emission of heat-rays from highly-heated gases, failed. 

Afterward, however, Dr. Siemens was convinced, by a quite simpleexperiment of a different kind, that his supposition was erroneous. Anordinary lamp, with circular wick, and short glass cylinder, was whollyscreened with a board, and a thermopile was so placed that its axis laysomewhat higher than the edge of the board. As the room-walls had prettymuch a uniform temperature, the deflection of the galvanometer was butslight, when the tube-axis of the thermopile was directed anywhereoutside of the hot-air current rising from the flame. When, however, theaxis was directed to this current, a deflection occurred, which was asgreat as that from the luminous flame itself. That the heat radiationfrom hot gases is but very small in comparison with that from equallyhot solid bodies, was shown by the large deflection produced when apiece of fine wire was held in the hot-air current. On the other hand, however, it was far too considerable to admit of being attributed todust particles suspended in the air current. 

It must be conceded to be possible (the author says) that the lightradiation of hot gases, as also the heat radiation, is only exceedinglyweak, and therefore may escape observation. It is, therefore, much tobe desired that the experiments should be repeated at still highertemperatures and with more exact instruments, in order to determinethe limit of temperature at which heated gases undoubtedly becomeself-incandescent. The fact, however, that gases, at a temperature ofmore than 1, 500° C, are not yet luminous, proves that the incandescenceof the flame is not to be explained as a self-incandescence of theproducts of combustion. This is confirmed by the circumstance that, withrapid mixture of the burning gases, the flame becomes shorter becausethe combustion process goes on more quickly, and hotter because lesscold air has access. Further, the flame also becomes shorter and hotterif the gases are strongly heated previous to combustion. As the risingproducts of combustion still retain for a time the temperature of theflame, the reverse must occur if the gases were self-luminous. Theluminosity of the flame, however, ceases at a sharp line of demarkation, and evidently coincides with completion of the chemical action. Thelatter, itself, therefore, and not the heating of the combustionproducts, which is due to it, must be the cause of the luminosity. Ifwe suppose that the gas-molecules are surrounded by an ether-envelope, then, in chemical combination of two or several such molecules, theremust occur a changed position of the ether-envelopes. The motion ofether-particles thus caused may be represented by vibrations, which formthe starting-point of light and heat-waves. 

In quite a similar manner we may also, according to Dr. Siemens, represent the light-phenomenon occurring when an electric currentis sent through gases, which always takes place when the maximum ofpolarization belonging to them is exceeded. As the passage of thecurrent through the gas seems to be always connected with chemicalaction, the phenomenon of glow may be explained in the same way as inflame, by oscillating transposition of the ether envelopes, by which thepassage of electricity is effected. In that case the light of flame maybe called electric light by the same light as the light of the ozonetube or the Geissler tube, which is mainly to be distinguished from theformer in that it contains a dielectric of an extremely small maximum ofpolarization. This correspondence in the causes of luminosity of flame, and of gases traversed by electric currents, is supported by thesimilarity of the flame-phenomena in strength and color of light. 

[These researches were lately described by Dr. Werner Siemens to theBerlin Academy. ]

 * * * * *

A QUICK WAY TO ASCERTAIN THE FOCUS OF A LENS. 

It is well known that if the size of an object be ascertained, thedistance of a lens from that object, and the size of the image depictedin a camera by that lens, a very simple calculation will give thefocus of the lens. In compound lenses the matter is complicated by therelative foci of its constituents and their distance apart; but theseitems, in an ordinary photographic objective, would so slightly affectthe result that for all practical purposes they may be ignored. 

What we propose to do--what we have indeed done--is to make two of theseterms constant in connection with a diagram, here given, so that a mereinspection may indicate, with its aid, the focus of a lens. All that isrequired in making use of it is to plant the camera perfectly upright, and place in front of it, at exactly fifteen feet from the center of thelens, a two foot rule, also perfectly upright and with its centerthe same height from the floor as the lens, and then, after focusingaccurately with as large a diaphragm as will give sharpness, to note thesize of the image and refer it to the diagram. The focus of the lensemployed will be marked under the line corresponding to the size of theimage of the rule on the ground glass. 

As our object is to minimize time and trouble to the utmost, we may makea suggestion or two as to carrying out the measuring. It will be obviousthat any object exactly two feet in length, rightly placed, will answerquite as well as a "two-foot, " which we selected as being about ascommon a standard of length and as likely to be handy for use asany. The pattern in a wall paper, a mark in a brick wall, a studiobackground, or a couple of drawing pins pressed into a door, so long astwo feet exactly are indicated, will answer equally well. 

And, further, as to the actual mode of measuring the image on theground glass (we may say that there is not the slightest need to takea negative), it will perhaps be found the readiest method to turn theglass the ground side outward, when two pencil marks may be made withcomplete accuracy to register the length of the image, which can then becompared with the diagram. Whatever plan is adopted, if the distance bemeasured exactly between lens and rule, the result will give the focuswith exactitude sufficient for any practical purpose. --_Br. Jour. OfPhoto_. 

[Illustration]

 * * * * *

THE HISTORY OF THE PIANOFORTE. 

[Footnote: A paper recently read before the Society of Arts, London. ]

By A. J. HIPKINS. 

As this paper is composed from a technical point of view, someelucidation of facts, forming the basis of it, is desirable before weproceed to the chronological statement of the subject. These facts arethe strings, and their strain or tension; the sound-board, which is theresonance factor; and the bridge, connecting it with the strings. Thestrings, sound-board, and bridge are indispensable, and common toall stringed instruments. The special fact appertaining to keyboardinstruments is the mechanical action interposed between the player andthe instrument itself. The strings, owing to the slender surface theypresent to the air, are, however powerfully excited, scarcely audible. To make them sufficiently audible, their pulsations have to becommunicated to a wider elastic surface, the sound-board, which, byaccumulated energy and broader contact with the air, re-enforces thestrings' feeble sound. The properties of a string set in periodicvibration are the best known of the phenomena appertaining to acoustics. The molecules composing the string are disturbed in the string'svibrating length by the means used to excite the sound, and run off intosections, the comparative length and number of which depend partly uponthe place in the string the excitement starts from; partly upon theforce and the form of force that is employed; and partly upon thelength, thickness, weight, strain, and elasticity of the string, withsome small allowance for gravitation. The vibrating sections are ofwave-like contour; the nodes or points of apparent rest being reallyknots of the greatest pressure from crossing streams of molecules. Wherethe pressure slackens, the sections rise into loops, the curves of whichshow the points of least pressure. Now, if the string be struck upon aloop, less energy is communicated to the string, and the carrying powerof the sound proportionately fails. If the string be struck upon a node, greater energy ensues, and the carrying power proportionately gains. By this we recognize the importance of the place of contact, orstriking-place of the hammer against the string; and the necessity, inorder to obtain good fundamental tone, which shall carry, of the notebeing started from a node. 

If the hammer is hard, and impelled with force, the string breaks intoshorter sections, and the discordant upper partials of the string, thusbrought into prominence, make the tone harsh. If the hammer is soft, andthe force employed is moderated, the harmonious partials of the longersections strike the ear, and the tone is full and round. By thefrequency of vibration, that is to say, the number of times a stringruns through its complete changes one way and the other, say, formeasurement, in a second of time, we determine the pitch, or relativeacuteness of the tone as distinguished by the ear. 

We know, with less exactness, that the sound-board follows similar laws. The formation of nodes is helped by the barring of the sound-board, a ribbing crosswise to the grain of the wood, which promotes theelasticity, and has been called the "soul" of stringed musicalinstruments. The sound-board itself is made of most carefully chosenpine; in Europe of the _Abies excelsa_, the spruce fir, which, when wellgrown, and of light, even grain, is the best of all woods for resonance. The pulsations of the strings are communicated to the sound-board by thebridge, a thick rail of close-grained beech, curved so as to determinetheir vibrating lengths, and attached to the sound-board by dowels. Thebridge is doubly pinned, so as to cut off the vibration at the edgeof the bearing the strings exert upon the bridge. The shock of eachseparate pulsation, in its complex form, is received by the bridge, and communicated to such undamped strings as may, by their lengths, besensitive to them; thus producing the Æolian tone commonly known assympathetic, an eminently attractive charm in the tone of a pianoforte. 

We have here strings, bridge, and sound-board, or belly, as it istechnically called, indispensable for the production of the tone, andindivisible in the general effect. The proportionate weight ofstringing has to be met by a proportionate thickness and barring of thesound-board, and a proportionate thickness and elevation of the bridge. 

The tension of the strings is met by a framing, which has become morerigid as the drawing power of the strings has been gradually increased. In the present concert grands of Messrs. Broadwood, that drawing powermay be stated as starting from 150 lb. For each single string in thetreble, and gradually increasing to about 300 lb. For each of the singlestrings in the bass. I will reserve for the historical description ofmy subject some notice of the different kinds of framing that have beenintroduced. It will suffice, at this stage, to say that it was at firstof wood, and became, by degrees, of wood and iron; in the present daythe iron very much preponderating. It will be at once evident that theobject of the framing is to keep the ends of the strings apart. The nearends are wound round the wrest-pins, which are inserted in the woodenbed, called the wrest-plank, the strength and efficiency of which aremost important for the tone and durability of the instrument. It iscomposed of layers of wainscot oak and beech, the direction of thegrain being alternately longitudinal and lateral. Some makers cover thewrest-plank with a plate of brass; in Broadwood's grands, it is a plateof iron, into which, as well as the wood, the wrest-pins are screwed. The tuner's business is to regulate the tension, by turning thewrest-pins, in which he is chiefly guided by the beats which becomeaudible from differing numbers of vibrations. The wrest-plank isbridged, and has its bearing like the soundboard; but the wrest-plankhas no vibrations to transfer, and should, as far as possible, offerperfect insensibility to them. 

I will close this introductory explanation with two remarks, made by thedistinguished musician, mechanician, and inventor, Theobald Boehm, ofMunich, whose inventions were not limited to the flute which bears hisname, but include the initiation of an important change in the modernpianoforte, as made in America and Germany. Of priority of invention hesays, in a letter to an English friend, "If it were desirable to analyzeall the inventions which have been brought forward, we should find thatin scarcely any instance were they the offspring of the brain of asingle individual, but that all progress is gradual only; each workerfollows in the track of his predecessor, and eventually, perhaps, advances a step beyond him. " And concerning the relative value ofinventions in musical instruments, it appears, from an essay of hiswhich has been recently published, that he considers improvement inacoustical proportions the chief foundation of the higher or lowerdegree of perfection in all instruments, their mechanism being but ofsecondary value. 

I will now proceed to recount briefly the history of the pianoforte fromthe earliest mention of that name, continuing it to our contemporaryinstruments, as far as they can be said to have entered into thehistorical domain. It has been my privilege to assist in proving thatBartolommeo Cristofori was, in the first years of the 18th century, the real inventor of the pianoforte, but with a wide knowledge andexperience of how long it has taken to make any invention in keyedinstruments practicable and successful, I cannot believe that Cristoforiwas the first to attempt to contrive one. I should rather accept hisgood and complete instrument as the sum of his own lifelong studies andexperiments, added to those of generations before him, which have leftno record for us as yet discovered. 

The earliest mention of the name pianoforte (_piano e forte_), appliedto a musical instrument, has been recently discovered by Count Valdrighiin documents preserved in the Estense Library, at Modena. It is datedA. D. 1598, and the reference is evidently to an instrument of the spinetor cembalo kind; but how the tone was produced there is no statement, no word to base an inference upon. The name has not been met withagain between the Estense document and Scipione Maffei's well-knowndescription, written in 1711, of Cristofori's "gravecembalo col piano eforte. " My view of Cristofori's invention allows me to think that theEstense "piano e forte" may have been a hammer cembalo, a very imperfectone, of course. But I admit that the opposite view of forte and piano, contrived by registers of spinet-jacks, is equally tenable. 

Bartolommeo Cristofori was a Paduan harpsichord maker, who was invitedby Prince Ferdinand dei Medici to Florence, to take charge of the largecollection of musical instruments the Prince possessed. At Florence heproduced the invention of the pianoforte, in which he was assisted andencouraged by this high-minded, richly-cultivated, and very musicalprince. Scipione Maffei tells us that in 1709 Cristofori had completedfour of the new instruments, three of them being of the usualharpsichord form, and one of another form, which he leaves undescribed. It is interesting to suppose that Handel may have tried one or more ofthese four instruments during the stay he made at Florence in 1708. Butit is not likely that he was at all impressed with the potentialities ofthe invention any more than John Sebastian Bach was in after years whenhe tried the pianofortes of Silbermann. 

The sketch of Cristofori's action in Maffei's essay, from which I havehad a working model accurately made, shows that in the first instrumentsthe action was not complete, and it may not have been perfected whenPrince Ferdinand died in 1713. But there are Cristofori grand pianospreserved at Florence, dated respectively 1720 and 1726, in which animproved construction of action is found, and of this I also exhibita model. There is much difference between the two. In the second, Cristofori had obtained his escapement with an undivided key, reconciling his depth of touch, or keyfall, with that of thecontemporary harpsichord, by driving the escapement lever through thekey. He had contrived means for regulating the escapement distance, andhad also invented the last essential of a good pianoforte action, thecheck. I will explain what is meant by escapement and check. When, bya key being put down, the hammer is impelled toward the strings, it isnecessary for their sustained vibration that, after impact, the hammershould rebound or escape; or it would, as pianoforte makers say, "block, " damping the strings at the moment they should sound. 

A dulcimer player gains his elastic blow by the free movement of thewrist. To gain a similarly elastic blow mechanically in his firstaction, Cristofori cut a notch in the butt of his hammer from which theescapement lever, "linguetta mobile" as he called it--"hopper, " as wecall it--being centered at the base, moved forward, when the key was putdown, to the extent of its radius, and after the delivery of the blowreturned to its resting place by the pressure of a spring. The firstaction gave the blow with more direct force than the second, which hadthe notch upon what is called the underhammer, but was defective inthe absence of any means to regulate the distance of the "go-off, " or"escapement" from the string. In the second action, a small check beforethe hopper is intended to regulate it, but does so imperfectly. Thepianoforte had to wait for fifty years for satisfactory regulation ofthe escapement. 

In the first action, the hammer rests in a silken fork, dropping thewhole distance of the rise of every blow. The check in the secondaction, the "paramartello, " is next in importance to the escapement. Itcatches the back part of the hammer at different points of the radius, responding to the amount of force the player has used upon the key. Sothat in repeated blows, the rise of the hammer is modified, and thenotch is nearer to the returning hopper in proportionate degree. 

I have given the first place in description to Cristofori's actions, instead of to the "cembalo" or instrument to which they were applied, because piano and forte, from touch, became possible through them, andwhat else was accomplished by Cristofori was due, primarily, to thedynamic idea. He strengthened his harpsichord sound-board againsta thicker stringing, renouncing the cherished sound-holes. Yet thesound-box notion clung to him, for he made openings in his sound-boardrail for air to escape. He ran a string-block round the case, entirelyindependent of the sound-board, and his wrest-plank, which also becamea separate structure, removed from the sound-board by the gap for thehammers, was now a stout oaken plank which, to gain an upward bearingfor the strings, he inverted, driving his wrest-pins through in themanner of a harp, and turning them in like fashion to the harp. He hadtwo strings to a note, but it did not occur to him to space them intopairs of unisons. He retained the equidistant harpsichord scale, andhad, at first, under-dampers, later over-dampers, which fell between theunisons thus equally separated. Cristofori died in 1731. He had pupils, one of whom made, in 1730, the, "Rafael d'Urbino, " the favoriteinstrument of the great singer Farinelli. The story of inventiveItalian pianoforte making ends thus early, but to Italy the inventionindisputably belongs. 

The first to make pianofortes in Germany was the famous Freibergorgan-builder and clavichord maker, Gottfried Silbermann. He submittedtwo pianofortes to the judgment of John Sebastian Bach in 1726, whichjudgment was, however, unfavorable; the trebles being found too weak, and the touch too heavy. Silbermann, according to the account of Bach'spupil, Agricola, being much mortified, put them aside, resolving not toshow them again unless he could improve them. We do not know what theseinstruments were, but it may be inferred that they were copies ofCristofori, or were made after the description of his invention byMaffei, which had already been translated from Italian into German, by Koenig, the court poet at Dresden, who was a personal friend ofSilbermann. With the next anecdote, which narrates the purchase of allthe pianofortes Silbermann had made, by Frederick the Great, we are uponsurer ground. This well accredited occurrence took place in 1746. Inthe following year occurred Bach's celebrated visit to Potsdam, when heplayed upon one or more of these instruments. Burney saw and describedone in 1772. I had this one, which was known to have remained in the newpalace at Potsdam until the present time unaltered, examined, and, by adrawing of the action, found it was identical with Cristofori's. Not, however, being satisfied with one example, I resolved to go myself toPotsdam; and, being furnished with permission from H. R. H. The CrownPrincess of Prussia, I was enabled in September, 1881, to set thequestion at rest of how many grand pianofortes by Gottfried Silbermannthere were still in existence at Potsdam, and what they were like. AtBerlin there are none, but at Potsdam, in the music-rooms of Frederickthe Great, which are in the town palace, the new palace, and SansSouci--left, it is understood, from the time of Frederick's deathundisturbed--there are three of these Silbermann pianofortes. All threeare with unimportant differences having nothing to do with structure, Cristofori instruments, wrest plank, sound-board, string-block, andaction; the harpsichord scale of stringing being still retained. Thework in them is undoubtedly good; the sound-boards have given in thetrebles, as is usual with old instruments, from the strain; but I shouldsay all three might be satisfactorily restored. Some other pianofortesseem to have been made in North Germany about this time, as our ownpoet Gray bought one in Hamburg in 1755, in the description of which wenotice the desire to combine a hammer action with the harpsichord whichso long exercised men's minds. 

The Seven Years' War put an end to pianoforte making on the linesSilbermann had adopted in Saxony. A fresh start had to be made a fewyears later, and it took place contemporaneously in South Germany andEngland. The results have been so important that the grand pianofortesof the Augsburg Stein and the London Backers may be regarded, practically, as reinventions of the instrument. The decade 1770-80 marksthe emancipation of the pianoforte from the harpsichord, of which beforeit had only been deemed a variety. Compositions appear written expresslyfor it, and a man of genius, Muzio Clementi, who subsequently became thehead of the pianoforte business now conducted by Messrs. Collard, cameforward to indicate the special character of the instrument, and foundan independent technique for it. 

A few years before, the familiar domestic square piano had beeninvented. I do not think clavichords could have been altered to squarepianos, as they were wanting in sufficient depth of case; but that thesuggestion was from the clavichord is certain, the same kind of case andkey-board being used. German authorities attribute the invention to anorgan builder, Friederici of Gera, and give the date about 1758 or 1760. I have advertised in public papers, and have had personal inquiry madefor one of Friederici's "Fort Biens, " as he is said to have called hisinstrument. I have only succeeded in learning this much--that Friedericiis considered to have been of later date than has been asserted in thetext-books. Until more conclusive information can be obtained, I mustbe permitted to regard a London maker, but a German by birth, JohannesZumpe, as the inventor of the instrument. It is certain that heintroduced that model of square piano which speedily became the fashion, and was chosen for general adoption everywhere. Zumpe began to makehis instruments about 1765. His little square, at first of nearly fiveoctaves, with the "old man's head" to raise the hammer, and "mopstick"damper, was in great vogue, with but little alteration, for forty years;and that in spite of the manifest improvements of John Broadwood'swrest-plank and John Geib's "grasshopper. " After the beginning of thiscentury, the square piano became much enlarged and improved by Collardand Broadwood, in London, and by Petzold, in Paris. It was overdone inthe attempt to gain undue power for it, and, about twenty years ago, sank in the competition, with the later cottage pianoforte, which wasalways being improved. 

To return to the grand pianoforte. The origin of the Viennese grand isrightly accredited to Stein, the organ builder, of Augsburg. I willcall it the German grand, for I find it was as early made in Berlin asVienna. According to Mozart's correspondence, Stein had made some grandpianos in 1777, with a special escapement, which did not "block"like the pianos he had played upon before. When I wrote the article"Pianoforte" in Dr. Grove's "Dictionary, " no Stein instrument wasforthcoming, but the result of the inquiries I had instituted at thattime ultimately brought one forward, which has been secured by thecurator of the Brussels Museum, M. Victor Mahillon. This instrument, with Stein's action and two unison scale, is dated 1780. Mozart's grandpiano, preserved at Salzburg, made by Walther, is a nearly contemporarycopy of Stein, and so also are the grands by Huhn, of Berlin, which Itook notes of at Berlin and Potsdam; the latest of these is dated 1790. 

An advance shown by these instruments of Stein and Stein's followers isin the spacing of the unisons; the Huhn grands having two strings toa note in the lower part of the scale, and three in the upper. TheCristofori Silbermann inverted wrest-plank has reverted to the usualform; the tuning pins and downward bearing being the same as in theharpsichord. There are no steel arches as yet between the wrest-plankand the belly-rail in these German instruments. As to Stein'sescapement, his hopper was fixed behind the key; the axis of the hammerrising on a principle which I think is older than Stein, but have notbeen able to trace to its source, and the position of his hammer isreversed. Stein's light and facile movement with shallow key-fall, resembling Cristofori's in bearing little weight, was gratefullyaccepted by the German clavichord players, and, reacting, became one ofthe determining agents of the piano music and style of playing of theVienna school. Thus arose a fluent execution of a rich figuration andbrilliant passage playing, with but little inclination to sonorousnessof effect, lasting from the time of Mozart's immediate followers to thatof Henri Herz; a period of half a century. Knee-pedals, as we translate"geuouillères, " were probably in vogue before Stein, and were leverspressed with the knees, to raise the dampers, and leave the pianoforteundamped, a register approved of by Carl Philip Emmanuel Bach, whoregarded the undamped pianoforte as the more agreeable for improvising.. He appears, however, to have known but little of the capabilities ofthe instrument, which seemed to him coarse and inexpressive beside hisfavorite clavichord. Stein appears to have made use of the "una corda"shift. Probably by knee-pedals, subsequently by foot-pedals, thefollowing effects were added to the Stein pianos. 

The harpsichord "harp"-stop, which muted one string of each note bya piece of leather, became, by the interposition of a piece of clothbetween the hammer and the strings, the piano, harp, or _celeste_. Themore complete sourdine, which muted all the strings by contact of a longstrip of leather, acted as the staccato, pizzicato, or pianissimo. TheGermans further displayed that ingenuity in fancy stops Mersenne hadattributed to them in harpsichords more than a hundred and fifty yearsbefore, by a bassoon pedal, a card which by a rotatory half-cylinderjust impinging upon the strings produced a reedy twang; also by pedalsfor triangle, cymbals, bells, and tambourine, the last drumming on thesound-board itself. 

Several of these contrivances may be seen in a six-pedal grandpianoforte belonging to Her Majesty the Queen, at Windsor Castle, bearing the name as maker of Stein's daughter, Nannette, who was afriend of Beethoven. The diagram represents the wooden framing of suchan instrument. 

We gather from Burney's contributions to "Rees's Cyclopaedia, " thatafter the arrival of John Christian Bach in London, A. D. 1759, a fewgrand pianofortes were attempted, by the second-rate harpsichord makers, but with no particular success. If the workshop tradition can be reliedupon that several of Silbermann's workmen had come to London about thattime, the so-called "twelve apostles, " more than likely owing to theSeven Years' War, we should have here men acquainted with the Cristoforimodel, which Silbermann had taken up, and the early grand pianosreferred to by Burney would be on that model. I should say the "newinstrument" of Messrs. Broadwood's play-bill of 1767 was such a grandpiano; but there is small chance of ever finding one now, and if aninstrument were found, it would hardly retain the original action, asMessrs. Broadwood's books of the last century show the practice ofrefinishing instruments which had been made with the "old movement. "

[Illustration: Fig. 1. ]

Burney distinguishes Americus Backers by special mention. He is saidto have been a Dutchman. Between 1772 and 1776, Backers produced thewell-known English action, which has remained the most durable and oneof the best up to the present day. It refers in direct leverage toCristofori's first action. It is opposite to Stein's contemporaryinvention, which has the hopper fixed. In the English action, as in theFlorentine, the hopper rises with the key. To the direct leverage ofCristofori's first action, Backers combined the check of the second, andthen added an important invention of his own, a regulating screw andbutton for the escapement. Backers died in 1776. It is unfortunate wecan refer to no pianoforte made by him. I should regard it as treasuretrove if one were forthcoming in the same way that brought to light theauthentic one of Stein's. As, however, Backers' intimate friends, andhis assistants in carrying out the invention, were John Broadwood andRobert Stodart, we have, in their early instruments, the principle andall the leading features of the Backers grand. The increased weightof stringing was met by steel arches placed at intervals between thewrest-plank and the belly-rail, but the belly-rail was still free fromthe thrust of the wooden bracing, the direction of which was confined tothe sides of the case, as it had been in the harpsichord. 

Stodart appears to have preceded Broadwood in taking up the manufactureof the grand piano by four or five years. In 1777 he patented analternate pianoforte and harpsichord, the drawing of which patent showsthe Backers action. The pedals he employed were to shift the harpsichordregister and to bring on the octave stop. The present pedals wereintroduced in English and grand pianos by 1785, and are attributed toJohn Broadwood, who appears to have given his attention at once to theimprovement of Backers' instrument. Hitherto the grand piano had beenmade with an undivided belly-bridge, the same as the harpsichord hadbeen; the bass strings in three unisons, to the lowest note, being ofbrass. Theory would require that the notes of different octaves shouldbe multiples of each other and that the tension should be the same foreach string. The lowest bass strings, which at that time were the noteF, would thus require a vibrating length of about twelve feet. As onlyhalf this length could be afforded, the difference had to be made up inthe weight of the strings and their tension, which led, in these earlygrands, to many inequalities. The three octaves toward the treble could, with care, be adjusted, the lengths being practically the ideal lengths. It was in the bass octaves (pianos were then of five octaves) theinequalities were more conspicuous. To make a more perfect scale andequalize the tension was the merit and achievement of John Broadwood, who joined to his own practical knowledge and sound intuitions the aidof professed men of science. The result was the divided bridge, the bassstrings being carried over the shorter division, and the most beautifulgrand pianoforte in its lines and curves that has ever been made wasthen manufactured. In 1791 he carried his scale up to C, five and ahalf octaves; in 1794 down to C, six octaves, always with care for theartistic, form. The pedals were attached to the front legs of the standon which the instrument rested. The right foot-pedal acted first asthe piano register, shifting the impact of each hammer to two unisonsinstead of three; a wooden stop in the right hand key-block permittedthe action to be shifted yet further to the right, and reducing the blowto one string only, produced the pianissimo register or _una corda_ ofindescribable attractiveness of sound. The cause of this was in thereflected vibration through the bridge to the untouched strings. Thepresent school of pianoforte playing rejects this effect altogether, butBeethoven valued it, and indicated its use in some of his great works. Steibert called the _una corda_ the _celeste_, which is more appropriateto it than Adam's application of this name to the harp-stop, by whichthe latter has gone ever since. 

Up to quite the end of the last century the dampers were continued tothe highest note in the treble. They were like harpsichord dampersraised by wooden jacks, with a rail or stretcher to regulate their rise, which served also as a back touch to the keys. I have not discovered theexact year when, or by whom, the treble dampers were first omitted, thus leaving that part of the scale undamped. This bold act gave theinstrument many sympathetic strings free to vibrate from the bridge whenthe rest of the instrument was played, each string, according to itslength, being an aliquot division of a lower string. This gave theinstrument a certain brightness or life throughout, an advantage whichhas secured its universal adoption. The expedients of an untouchedoctave string and of utilizing those lengths of wire that lie beyond thebridges have been brought into notice of late years, but the latter wasearly in the century essayed by W. F. Collard. 

From difficulties of tuning, owing to friction and other causes, thereal gain of these expedients is small, and when we compare them withthe natural resources we have always at command in the normal scaleof the instrument, is not worth the cost. The inventor of the damperregister opened a floodgate to such aliquot re-enforcement as can be gotin no other way. Each lower note struck of the undamped instrument, by excitement from the sound-board carried through the bridge, setsvibrating higher strings, which, by measurement, are primes to itspartials; and each higher string struck calls out equivalent partialsin the lower strings. Even partials above the primes will excitetheir equivalents up to the twelfth and double octave. What a glow oftone-color there is in all this harmonic re-enforcement, and who wouldnow say that the pedals should never be used? By their proper use, the student's ear is educated to a refined sense of distinction ofconsonance and dissonance, and the intention and beauty of Chopin'spedal work becomes revealed. 

The next decade, 1790-1800, brings us to French grand pianoforte-making, which was then taken up by Sebastian Erard. This ingenious mechanic andinventor traveled the long and dreary road along which nearly all whohave tried to improve the pianoforte have had to journey. He appears, atfirst, to have adopted the existing model of the English instrument inresonance, tension, and action, and to have subsequently turned hisattention to the action, most likely with the idea of combining theEnglish power of gradation with the German lightness of touch. Erardclaimed, in the specification to a patent for an action, dated 1808, "the power of giving repeated strokes, without missing or failure, byvery small angular motions of the key itself. "

Once fairly started, the notion of repetition became the dominant ideawith pianoforte-makers, and to this day, although less insisted upon, engrosses time and attention that might be more usefully directed. Somegreat players, from their point of view of touch, have been downrightopposed to repetition actions. I will name Kalkbrenner, Chopin, and, inour own day, Dr. Hans von Bülow. Yet the Erard's repetition, in the formof Hertz's reduction, is at present in greater favor in America andGermany, and is more extensively used, than at any previous period. 

The good qualities of Erard's action, completed in 1821, the germ ofwhich will be found in the later Cristofori, are not, however, due torepetition capability, but to other causes, chiefly, I will say, tocounterpoise. The radical defect of repetition is that the repeatednote can never have the tone-value of the first; it depends upon themechanical contrivance, rather than the finder of the player, which isdirectly indispensable to the production of satisfactory tone. When thesensibility of the player's touch is lost in the mechanical action, thecorresponding sensibility of the tone suffers; the resonance is not, somehow or other, sympathetically excited. 

Erard rediscovered an upward bearing, which had been accomplished byCristofori a hundred years before, in 1808. A down-bearing bridge to thewrest-plank, with hammers striking upward, are clearly not in relation;the tendency of the hammer must be, if there is much force used, tolift the string from its bearing, to the detriment of the tone. Erardreversed the direction of the bearing of the front bridge, substitutingfor a long, pinned, wooden bridge, as many little brass bridges as therewere notes. The strings passing through holes bored through the littlebridges, called agraffes, or studs, turned upward toward the wrest-pin. By this the string was forced against its rest instead of off it. Itis obvious that the merit of this invention would in time make its usegeneral. A variety of it was the long brass bridge, specially usedin the treble on account of the pleasant musical-box like tone itsvibration encouraged. Of late years another upward bearing has foundfavor in America and on the Continent, the Capo d'Astro bar of M. Bord, which exerts a pressure upon the strings at the bearing point. 

About the year 1820, great changes and improvements were made in thegrand pianoforte both externally and in the instrument. The harpsichordboxed up front gave way to the cylinder front, invented by Henry Pape, a clever German pianoforte-maker who bad settled in Paris. Who put thepedals upon the familiar lyre I have not been able to learn. It wouldbe in the Empire time, when a classical taste was predominant. But thegreatest change was from a wooden resisting structure to one in whichiron should play an important part. The invention belongs to thiscountry, and is due to a tuner named William Allen, a young Scotchman, who was in Stodart's employ. With the assistance of the foreman, Thom, the invention was completed, and a patent was taken out, dated the 15thof January, 1820, in which Thom was a partner. The patent was, however, at once secured by the Stodarts, their employers. The object of thepatent was a combination of metal tubes with metal plates, the metallictubes extending from the plates which were attached to the string-blockto the wrest-plank. The metal plates now held the hitch-pins, to whichthe farther ends of the strings were fixed, and the force of the tensionwas, in a great measure, thrown upon the tubes. The tubes were amistake; they were of iron over the steel strings, and brass over thebrass and spun strings, the idea being that of the compensation oftuning when affected by atmospheric change, also a mistake. However, the tubes were guaranteed by stout wooden bars crossing them at rightangles. At once a great advance was made in the possibility of usingheavier strings, and the great merit of the invention was everywhererecognized. 

James Broadwood was one of the first to see the importance of theinvention, if it were transformed into a stable principle. He had triediron tension bars in past years, but without success. It was now due tohis firm to introduce a fixed stringed plate, instead of plates intendedto shift, and in a few years to combine this plate with four solidtension bars, for which combination he, in 1827, took out a patent, claiming as the motive for the patent the string-plate; the manner offixing the hitch-pins upon it, the fourth tension bar, which crossed theinstrument about the middle of the scale, and the fastening of that barto the wooden brace below, now abutting against the belly-rail, theattachment being effected by a bolt passing through a hole cut in thesound-board. 

This construction of grand pianoforte soon became generally adopted inEngland and France. Messrs. Erard, who appear to have had their ownadaptation of tension bars, introduced the harmonic bar in 1838. This, a short bar of gun metal, was placed upon the wrest-plank immediatelyabove the bearings of the treble, and consolidated the plank by screwstapped into it of alternate pressure and drawing power. In the originalinvention a third screw pressed upon the bridge. By this bar a verylight, ringing treble tone was gained. This was followed by a longharmonic bar extending above the whole length of the wrest-plank, whichit defends from any tendency to rise, by downward pressure obtained byscrews. During 1840-50, as many as five and even six tension bars wereused in grand pianofortes, to meet the ever increasing strain ofthicker stringing. The bars were strutted against a metal edging to thewrest-plank, while the ends were prolonged forward until they abuttedagainst its solid mass on the key-board side of the tuning-pins. Thespace required for fixing them cramped the scale, while the strings weredivided into separate batches between them. It was also difficult toso adjust each bar that it should bear its proportionate share of thetension; an obvious cause of inequality. 

Toward the end of this period a new direction was taken by Mr. HenryFowler Broadwood, by the introduction of an iron-framed pianoforte, inwhich the bars should be reduced in number, and with the bars the steelarches, as they were still called, although they were no longer archesbut struts. 

In a grand pianoforte, made in 1847, Mr. Broadwood succeeded inproducing an instrument of the largest size, practically depending uponiron alone. Two tension bars sufficed, neither of them breaking into thescale: the first, nearly straight, being almost parallel with the lowestbass string; the second, presenting the new feature of a diagonal barcrossed from the bass corner to the string-plate, with its thrust at anangle to the strings. 

There were reasons which induced Mr. Broadwood to somewhat modify andimprove this framing, but with the retention of its leading feature, thediagonal bar, which was found to be of supreme importance in bearing thetension where it is most concentrated. From 1852, his concert grandshave had, in all, one bass bar, one diagonal bar, a middle bar witharch beneath, and the treble cheek bar. The middle bar is the only onedirectly crossing the scale, and breaking it. It is strengthened byfeathered ribs, and is fastened by screws to the wooden brace below. Thethree bars and diagonal bar, which is also feathered, abut firmly on thestring plate, which is fastened down to the wooden framing by screws. Since 1862, the wooden wrest-plank has been covered with a plate ofiron, the iron screw-pin plate bent at a right angle in front. Thewrest-pins are screwed into this plate, and again in the wood below. The agraffes, which take the upward bearings of the strings, are firmlyscrewed into this plate. The long harmonic bar of gun metal liesimmediately above the agraffes, and crossing the wrest-plank in itsentire width, serves to keep it, at the bearing line, in position. Thisconstruction is the farthest advance of the English pianoforte. 

[Illustration: FIG. 2. --WILLIAM ALLEN. ]

Almost simultaneously with it has arisen a new development in America, which, beginning with Conrad Meyer, about 1833, has been advanced by theChickerings and Steinways to the well known American and German grandpianoforte of the present day. It was perfected in America about in1859, and has been taken up since by the Germans almost universally, andwith very little alteration. Two distinct principles have been developedand combined--the iron framing in a single casting, and the cross oroverstringing. I will deal with the last first, because it originated inEngland and was the invention of Theobald Boehm, the famous improver ofthe flute. In Grove's "Dictionary, " I have given an approximate date tohis overstringing as 1835, but reference to Boehm's correspondence withMr. Walter Broadwood shows me that 1831 was really the time, andthat Boehm employed Gerock and Wolf, of 79 Cornhill, London, musicalinstrument makers, to carry out his experiment. Gerock being opposedto an oblique direction of the strings and hammers, Boehm found a morewilling coadjutor in Wolf. As far as I can learn, a piccolo, a cabinet, and a square piano were thus made overstrung. Boehm's argument was thata diagonal was longer within a square than a vertical, which, as hesaid, every schoolboy knew. The first overstrung grand pianos seen inLondon were made by Lichtenthal, of St. Petersburg; not so much for toneas for symmetry of the case; two instruments so made were among thecuriosities of the Great Exhibition of 1851. Some years before this, Henry Pape had made experiments in cross stringing, with the intentionto economize space. His ideas were adopted and continued by the Londonmaker, Tomkisson, who acquired Pape's rights for this country. The ironframing in a single casting is a distinctly American invention, butproceeding, like the overstringing, from a German by birth. The ironcasting for a square piano of the American Alpheus Babcock, may havesuggested Meyer's invention; it was, however, Conrad Meyer, who, in Philadelphia, and in 1833, first made a real iron frame squarepianoforte. The gradual improvement upon Meyer's invention, during thenext quarter of a century, are first due to the Chickerings and thenthe Steinways. The former overstrung an iron frame square, the latteroverstrung an iron frame grand, the culmination of this special makesince of general American and German adoption. It will be seen that, inthe American make, the number of tension bars has not been reduced, buta diagonal support has, to a certain extent, been accepted and adopted. The sound-board bridges are much further apart than obtains with theEnglish grand, or with the Anglo-French Erard. The advocates of theAmerican principle point out the advantages of a more open scale, andmore equal pressure on the sound-board. They likewise claim, as a gain, a greater tension. I have no quite accurate information as to whatthe sum of the tension may be of an American grand piano. One ofBroadwood's, twenty years ago, had a strain of sixteen and one-halftons; the strain has somewhat increased since then. The remarkableimprovement in wiredrawing which has been made in Birmingham, Vienna, and Nuremberg, of late years, has rendered these high tensions of fareasier attainment than they would have been earlier in the century. 

[Illustration: FIG. 3. --BROADWOOD. ]

For me the great drawback to one unbroken casting is in the vibratoryring inseparable from any metal system that has no resting places tobreak the uniform reverberation proceeding from metal. We have alreadyseen how readily the strings take up vibrations which are only purewhen, as secondary vibrations, they arise by reversion from thesound-board. If vibration arises from imperfectly elastic wood, we heara dull wooden thud; if it comes from metal, partials of the strings arere-enforced that should be left undeveloped, which give a false ring tothe tone, and an after ring that blurs _legato_ playing, and nullifiesthe _staccato_. I do not pose as the obstinate advocate of parallelstringing, although I believe that, so far, it is the most logical andthe best; the best, because the left hand division of the instrument isfree from a preponderance of dissonant high partials, and we hear thelight and shade, as well as the cantabile of that part, better than byany overstrung scale that I have yet met with. I will not, I say, offera final judgment, because there may come a possible improvement of theoverstrung or double diagonal scale, if that scale is persisted in, andinventive power is brought to bear upon it, as valuable as that whichhas carried the idea thus far. 

[Illustration: FIG. 4. --BROADWOOD. ]

I have not had time to refer other than incidentally to the squarepianoforte, which has become obsolete. I must, however, give a separatehistorical sketch of the upright pianoforte, which has risen intogreat favor and importance, and in its development--I may say itsinvention--belongs to this present 19th century. The form has alwaysrecommended the upright on the score of convenience, but it was longbefore it occurred to any one to make an upright key board instrumentreasonably. Upright harpsichords were made nearly four hundred yearsago. A very interesting 17th century one was sold lately in thegreat Hamilton sale--sold, I grieve to say, to be demolished for itspaintings. But all vertical harpsichords were horizontal ones, put onend on a frame; and the book-case upright grand pianos, which, from theeighties, were made right into the present century, were horizontalgrands similarly elevated. The real inventor of the upright piano, inits modern and useful form, was that remarkable Englishman, John IsaacHawkins, the inventor of ever-pointed pencils; a civil engineer, poet, preacher, and phrenologist. While living at Border Town, New Jersey, U. S. A. , Hawkins invented the cottage piano--portable grand, he calledit--and his father, Isaac Hawkins, to whom, in Grove's "Dictionary, "I have attributed the invention, took out, in the year 1800[1], theEnglish patent for it. I can fortunately show you one of these originalpianinos, which belongs to Messrs. Broadwood. It is a wreck, but youwill discern that the strings descend nearly to the floor, while thekey-board, a folding one, is raised to a convenient height between thefloor and the upper extremities of the strings. Hawkins had an ironframe and tension rods, within which the belly was entirely suspended;a system of tuning by mechanical screws; an upper metal bridge; equallength of string throughout; metal supports to the action, in which alater help to the repetition was anticipated--the whole instrument beingindependent of the case. Hawkins tried also a lately revived notion ofcoiled strings in the bass, doing away with tension. Lastly, he soughtfor a _sostinente_, which has been tried for from generation togeneration, always to fail, but which, even if it does succeed, willproduce another kind of instrument, not a pianoforte, which owes so muchof its charm to its unsatiating, evanescent tone. 

[Transcribers note 1: 3rd digit illegible, best guess from context. ]

[Illustration: Fig. 5. --MEYER. ]

Once introduced into Hawkins' native country, England, the rise of theupright piano became rapid. In 1807, at latest, the now obsolete highcabinet piano was fairly launched. In 1811, Wornum produced a diagonal. In 1813, a vertical cottage piano. Previously, essays had been made toplace a square piano upright on its side, for which Southwell, an Irishmaker, took out a patent in 1798; and I can fortunately show you one ofthese instruments, kindly lent for this paper by Mr. Walter Gilbey. Ihave also been favored with photographs by Mr. Simpson, of Dundee, of aprecisely similar upright square. I show his drawing of the action--theSouthwell sticker action. W. F. Collard patented another similarexperiment in 1811. At first the sticker action with a leather hingeto the hammer-butt was the favorite, and lasted long in England. TheFrench, however, were quick to recognize the greater merit of Wornum'sprinciple of the crank action, which, and strangely enough throughFrance, has become very generally adopted in England, as well as Germanyand elsewhere. I regret I am unable to show a model of the originalcrank action, but Mr. Wornum has favored me with an early engraving ofhis father's invention. It was originally intended for the high cabinetpiano, and a patent was taken out for it in 1826. But many difficultiesarose, and it was not until 1829 that the first cabinet was so finished. Wornum then applied it in the same year to the small upright--thepiccolo, as he called it--the principle of which was, through Pleyel andPape, adopted for the piano manufacture in Paris. Within the last fewyears we have seen the general introduction of Bord's little pianino, called in England, ungrammatically enough, pianette, in the action ofwhich that maker cleverly introduced the spiral spring. And, also, ofthose large German overstrung and double overstrung upright pianos, which, originally derived from America, have so far met with favor andsale in this country as to induce some English makers, at least in theprinciple, to copy them. 

[Illustration: Fig. 6. --STEINWAY. ]

I will conclude this historical sketch by remarking, and as a remarkablehistorical fact, that the English firms which in the last centuryintroduced the pianoforte, to whose honorable exertions we owe a debt ofgratitude, with the exception of Stodart, still exist, and are in thefront rank of the world's competition. I will name Broadwood (whose flagI serve under), Collard (in the last years of the last century knownas Longman and Clementi), Erard (the London branch), Kirkman, and, Ibelieve, Wornum. On the Continent there is the Paris Erard house; and, at Vienna, Streicher, a firm which descends directly from Stein ofAugsburg, the inventor of the German pianoforte, the favorite of Mozart, and of Beethoven in his virtuoso period, for he used Stein's grands atBonn. Distinguished names have risen in the present century, some ofwhom have been referred to. To those already mentioned, I should liketo add the names of Hopkinson and Brinsmead in England; Bechstein andBluthner in Germany; all well-known makers. 

 * * * * *

THE POISONOUS PROPERTIES OF NITRATE OF SILVER, AND A RECENT CASE OFPOISONING WITH THE SAME. 

[Footnote: Read before the Medico Legal Society, April 5, 1883. ]

By HENRY A. MOTT, JR. , Ph. D. , etc. 

Of the various salts of silver, the nitrate, both crystallized and insticks (lunar caustic, _Lapis infernalis_), is the only one interestingto the toxicologist. 

This salt is an article of commerce, and is used technically andmedicinally. 

Its extensive employment for marking linen, in the preparation ofvarious hair dyes (Eau de Perse, d'Egypte, de Chiene, d'Afrique), in thephotographer's laboratory, etc. , affords ample opportunity to use thesame for poisoning purposes. 

Nitrate of silver possesses an acrid metallic taste and acts as aviolent poison. 

When injected into a vein of an animal, even in small quantities, thesymptoms produced are dyspnoea, [1] choking, spasms of the limbs and thenof the trunk, signs of vertigo, consisting of inability to stand erector walk steadily, and, finally retching and vomiting, and death byasphyxia. These symptoms, which have usually been attributed to thecoagulating action of the salt upon the blood, have been shown not todepend upon that change, which, indeed, does not occur, but upon adirect paralyzing operation upon the cerebro-spinal centers and uponthe heart; but the latter action is subordinate and secondary, and theformer is fatal through asphyxia. 

[Footnote 1: Nat. Dispensatory. Alf. Stille & John M. Maisch, Phila. , 1879, p. 232. ]

One-third of a grain injected into the jugular vein killed a dog in fourand one-half hours, with violent tetanic spasms. [1]

[Footnote 1: Medical Jurisprudence. Thomas S. Traill, 1857, p 117. ]

Devergie states that acute poisoning with nitrate of silver, administered in the shape of pills, is more frequent than one wouldsuppose. Yet Dr. Powell[1] states that it should always be given inpills, as the system bears a dose three times as large as when given insolution. The usual dose is from one-quarter of a grain to one grainthree times a day when administered as a medicine. In cases of epilepsyDr. Powell recommends one grain at first, to be gradually increasedto six. Clocquet[2] has given as much as fifteen grains in a day, andRicord has given sixteen grains of argentum chloratum ammoniacale. 

[Footnote 1: U. S. Dispensatory, 18th ed. , p. 1049. Wood & Bache. ]

[Footnote 2: Handbuch der Giftlehre, von A. W. M. Von Hasselt. 1862, p. 316. ]

Cases of poisoning have resulted from sticks of lunar caustic gettinginto the stomach in the process of touching the throat (Boerhave)[1];in one case, according to Albers, a stick of lunar caustic got into thetrachea. 

[Footnote 1: Virchow's Archiv, Bd. Xvii. , s. 135. 1859. ]

Von Hasselt therefore urges the utmost caution in using lunar caustic;the sticks and holder should always be carefully examined before use. An apprentice[1] to an apothecary attempted to commit suicide by takingnearly one ounce of a solution of nitrate of silver without fatalresult. It must be remarked, however, that the strength of the solutionwas not stated. 

[Footnote 1: Handbuch der Giftlehre, von A. W. M. Von Hasselt. ZweiterTheil, 1862. P. 316. ]

In 1861, a woman, fifty-one years old, died in three days from theeffects of taking a six-ounce mixture containing fifty grains of nitrateof silver given in divided doses. [1] She vomited a brownish yellow fluidbefore death. The stomach and intestines were found inflamed. It isstated that silver was found in the substance of the stomach and liver. 

[Footnote 1: Treatise on Poison. Taylor, 1875, p. 475. ]

It is evident that the poisonous dose, when taken internally, is not sovery small, but still it would not be safe to administer much over theamounts prescribed by Ricord, for in the case of the dog mentioned onethird of a grain injected into the jugular vein produced death in fourand one-half hours. 

The circumstance that more can be taken internally is explained by therapid decomposition to which this silver salt is liable in the body bythe proteine substance and chlorine combinations in the stomach, thehydrochloric acid in the gastric juice, and salt from food. 

The first reaction produced by taking nitrate of silver internally is acombination of this salt with the proteinaceous tissues with which itcomes in contact, as also a precipitation of chloride of silver. 

According to Mitscherlich, the combination with the proteine oralbuminous substance is not a permanent one, but suffers a decompositionby various acids, as dilute acetic and lactic acid. 

The absorption of the silver into the system is slow, as the albuminoidand chlorine combinations formed in the intestinal canal cannot beimmediately dissolved again. 

In the tissues the absorbed silver salt is decomposed by the tissues, and the oxide and metallic silver separate. 

Partly for this reason and partly on account of the formation of thesolid albuminates, etc. , the elimination of the silver from the bodytakes place very slowly. Some of the silver, however, passed out in thefæces, and, according to Lauderer, Orfila, and Panizza, some can bedetected in the urine. 

Bogolowsky[1] has also shown that in rabbits poisoned with preparationsof silver, the (often albuminous) urine and the contents of the (veryfull) gall bladder contained silver. 

[Footnote 1: Arch. F. Path. Anatomie, xlvi. , p. 409. Gaz. Med de Paris, 1868, No. 39. Also Journ. De l'Anatomie et de la Physiologie, 1873, p. 398. ]

Mayencon and Bergeret have also shown that in men and rabbits the silversalt administered is quickly distributed in the body, and is but slowlyexcreted by the urine and fæces. 

Chronic poisoning shows itself in a peculiar coloring of the skin(Argyria Fuchs), especially in the face, beginning first on thesclerotic. The skin does not always take the same color; it becomes inmost cases grayish blue, slaty sometimes, though, a greenish brown orolive color. 

Von Hasselt thinks that probably chloride of silver is deposited inthe rete malpighii, which is blackened by the action of light, or thatsulphide of silver is formed by direct union of the silver with thesulphur of the epidermis. That the action of light is not absolutelynecessary, Patterson states, follows from the often simultaneousappearance of this coloring upon the mucous membrane, especially that ofthe mouth and upon the gums; and Dr. Frommann Hermann[1] and others haveshown that a similar coloring is also found in the internal parts. 

[Footnote 1: Leh der Experiment. Tox. Dr. Hermann, Berlin, 1874, p. 211. ]

Versmann found 14. 1 grms. Of dried liver to contain 0. 009 grm. Chlorideof silver, or 0. 047 per cent. Of metallic silver. In the kidneys hefound 0. 007 grm. Chloride of silver, or 0. 061 per cent. Of metallicsilver; this was in a case of chronic poisoning, the percentage will beseen to be very small. Orfila Jun. Found silver in the liver five monthsafter the poisoning. 

Lionville[1] found a deposit of silver in the kidneys, suprarenal gland, and plexus choroideus of a woman who had gone through a cure with lunarcaustic five years before death. 

[Footnote 1: Gaz. Med. , 1868. No. 39. ]

Sydney Jones[1] states that in the case of an old epileptic who had beenaccustomed to take nitrate of silver as a remedy, the choroid plexuseswere remarkably dark, and from their surface could be scraped a brownishblack, soot-like material, and a similar substance was found lying quitefree in the cavity of the fourth ventricle, apparently detached from thechoroid plexus. 

[Footnote 1: Trans. Path. Soc. , xi. Vol. ]

Attempts at poisoning for suicidal purposes with nitrate of silverare in most cases prevented from the fact that this salt has such adisagreeable metallic taste as to be repulsive; cases therefore ofpoisoning are only liable to occur by accident or by the willfuladministration of the poison by another person. 

Such a case occurred quite recently, to a very valuable mare belongingto August Belmont. 

I received on Dec. 6, 1882, a sealed box from Dr. Wm. J. Provost, containing the stomach, heart, kidney, portion of liver, spleen, andportion of rectum of this mare for analysis. 

Dr. Provost reported to me that the animal died quite suddenly, and thatthere was complete paralysis of the hind quarters, including rectum andbladder. 

The total weight of the stomach and contents was 18 lb. , the stomachitself weighing 3 lb. And 8 oz. 

Portions were taken from each organ, weighed, and put in alcohol foranalysis. 

The contents of the stomach were thoroughly mixed together and measured, and a weighed portion preserved for analysis. 

The stomach, when cut open, was perfectly white on its inner surface, and presented a highly corroded appearance. 

The contents of the stomach were first submitted to qualitativeanalysis, and the presence of a considerable quantity of nitrate ofsilver was detected. 

The other organs were next examined, and the presence of silver wasreadily detected, with the exception of the heart!

The liver had a very dark brown color. A quantitative analysis of thecontents of the stomach gave 59. 8 grains of nitrate of silver. In theliver 30. 5 grains of silver, calculated as nitrate, were found (averageweight, 11 lb. ). From the analysis made there was reason to believe thatat least one-half an ounce of nitrate of silver was given to the animal. Some naturally passed out in the fæces and urine. 

I was able to prepare several globules of metallic silver, as also allthe well known chemical combinations, such as sulphide, chloride, oxide, iodide, bromide, bichromate of silver, etc. 

From the result of my investigation I was led to the conclusion that theanimal came to death by the willful administering of nitrate of silver, probably mixed with the food. 

The paralysis of the hind quarters, mentioned by Dr. Provost, accordsperfectly with the action of this poison, as it acts on the nervecenters, especially the cerebro-spinal centers, and produces spasms ofthe limbs, then of the trunk, and finally paralysis. 

I might also state in this connection that, only two weeks previousto my receiving news of the poisoning of the mare, I examined forMr. Belmont the contents of the stomach of a colt which died verymysteriously, and found large quantities of corrosive sublimate to bepresent. 

Calomel is often given as a medicine, but not so with corrosivesublimate, which is usually employed in the arts as a poison. 

It is to be regretted that up to the present moment, even with the bestdetectives, the perpetrator of this outrage has been at large. Surelythe very limit of the law should be exercised against any man who wouldwillfully poison an innocent animal for revenge upon an individual. Cases have been reported in England where one groom would poison thecolts under the care of another groom, so that the owner would dischargetheir keeper and promote the other groom to his place. 

A few good examples, in cases where punishment was liberally meted out, would probably check such unfeeling outrages. 

 * * * * *

TUBERCLE BACILLI IN SPUTA. 

Prof. Baumgarten has just published in the _Ctbl. F. D. Med. Wiss_. , 25, 1882, the following easy method to detect in the expectorated matter ofphthisical persons the pathogenic tubercle bacilli:

Phthisical sputa are dried and made moist with very much diluted potashlye (1 to 2 drops of a 33 per cent. Potash lye in a watch glass ofdistilled water). The tubercle bacilli are then easily recognized with amagnifying power of 400 to 500. By light pressure upon the cover glassthe bacilli are easily pressed out of the masses of detritus andsecretion. To prevent, however, the possibility of mistaking thetubercle bacilli for other septic bacteria, or vice versa, the followingprocedure is necessary: After the examination just mentioned, the coverglass is lifted up and the little fluid sticking to its under sideallowed to dry, which is done within one or two minutes. Now the coverglass is drawn two or three times rapidly through a gas flame; onedrop of a diluted (but not too light) common watery aniline solution(splendid for this purpose is the watery extract of a common aniline inkpaper) is placed upon the glass. When now brought under the microscope, all the septic bacteria appear colored intensely blue, while thetubercle bacilli are absolutely colorless, and can be seen as clearly asin the pure potash lye. We may add, however, that Klebs considers hisown method preferable. 

As the whole procedure does not take longer than ten minutes, it is tobe recommended in general practice. The consequences of Koch's importantdiscovery become daily more apparent, and their application morepracticable. 

 * * * * *

[Concluded from SUPPLEMENT No. 384, page 6132. ]

MALARIA. 

By JAMES H. SALISBURY, A. M. , M. D. 

PRIZE ESSAY OF THE ALBANY MEDICAL COLLEGE ALUMNI ASSOCIATION, FEB. , 1882. 

VIII. 

Observations in Washington, D. C. , September 5, 1879, 8:35 A. M. , Bostontime, near Congressional Cemetery. 

1. Seized with sneezing on my way to cemetery. Examined nasal excretionsand found no Palmellæ. 

2. Pool near cemetery. Examined a spot one inch in diameter, raisedin center, green, found Oedegonium abundant. Some desmids, Cosmariumbinoculatum plenty. One or two red Gemiasmas, starch, Protuberanslamella, Pollen. 

3. Specimen soft magma of the pool margin. Oedogonium abundant, spores, yeast plants, dirt. 

4. Sand scraped. No organized forms but pollen, and mobile spores ofsome cryptogams. 

5. Dew on grass. One stellate compound plant hair, one Gemiasma verdans, two pollen. 

6. Grass flower dew. Some large white sporangia filled with spores. 

7. Grass blade dew, not anything of account. One pale Gemiasma, threeblue Gemiasmas, Cosmarium, Closterium. Diatoms, pollen, found ingreenish earth and wet with the dew. Remarks: Observations made at thepool with clinical microscope, one-quarter inch objective. Day cloudy, foggy, hot. 

8. Green earth in water way from pump near cemetery. Anabaina plentiful. Diatoms, Oscillatoriaceæ. Polycoccus species. Pollen, Cosmarium, Leptothrix, Gemiasma, old sporangia, spores many. Fungi belonging tofruit. Puccinia. Anguillula fluviatilis. 

9. Mr. Smith's blood. Spores, enlarged white corpuscles. Two sporangia?Gemiasma dark brown, black. Mr. Smith is superintendent CongressionalCemetery. Lived here for seven years. Been a great sufferer with ague. Says the doctors told him that they could do no more for him than hecould for himself. So he used Ayer's ague cure with good effect for sixmonths. Then he found the best effect from the use of the Holman liverague pad in his own case and that of his children. From his account onewould infer that, notwithstanding the excellence of the ague pad, whenhe is attacked, he uses blue mass, followed with purgatives, then 20grains of quinine. Also has used arsenic, but it did not agree with him. Also used Capsicum with good results. Had enlarged spleen; not so now. 

2d specimen of Mr. Smith's blood. Stelline, no Gemiasma. 3d specimen, do. One Gemiasma. 4th specimen. None. 5th specimen. Skin scraped showedno plants. 6th specimen. Urine; amyloid bodies; spores; no sporangia. 

United States Magazine store grounds. Observation 1. Margin ofEastern Branch River. Substance from decaying part of a water plant. Oscillatoriaceæ. Diatoms. Anguillula. Chytridium. Dirt. No Gemiasma. 

Observation 2. Moist soil. Near by, amid much rubbish, one or twoso-called Gemiasmas; white, clear, peripheral margin. 

Observation 3. Green deposit on decaying wood. Oscillatoriaceæ. Protuberans lamella, Gemiasma alba. Much foreign matter. 

Mr. Russell, Mrs. R. , Miss R. , residents of Magazine Grounds presentedno ague plants in their blood. Sergeant McGrath, Mrs. M. , Miss M. , presented three or four sporangias in their blood. Dr. Hodgkins, some inurine. Dr. H. 's friend with chills, not positive as to ague. No plantsfound. 

Observations in East Greenwich, R. I. , Aug. 16, 1877. 

1. At early morn I examined greenish earth, northwest of the town alongthe margin of a beautiful brook. Found the Protuberans lamella, theGemiasma alba and rubra. Observation 2. Found the same. Observation 3. Found the same. 

Observation 4. Salt marsh below the railroad bridge over the river. 

The scrapings of the soil showed beautiful yellow and transparentProtuberans, beautiful green sporangias of the Gemiasma verdans. 

Observation 5. Near the brook named was a good specimen of the Gemiasmaplumba. While I could not find out from the lay people I asked that anyague was there, I now understand it is all through that locality. 

Observation at Wellesley, Mass. , Aug. 20, 1877. 

No incrustation found. Examined the vegetation found on the margin ofthe Ridge Hills Farm pond. Among other things I found an Anguillulafluviatilis. Abundance of microspores, bacteria. Some of the Protococci. Gelatinous masses, allied to the protuberans, of a light yellow colorscattered all over with well developed spores, larger than those foundin the Protuberans. One or two oval sporanges with double outlines. Thisobservation was repeated, but the specimens were not so rich. Anotherspecimen from the same locality was shown to be made up of mosses by thevenation of leaves. 

Mine host with whom I lodged had a microscopical mount of theProtococcus nivalis in excellent state of preservation. The sporangiawere very red and beautiful, but they showed no double cell wall. 

In this locality ague is unknown; indeed, the place is one of unusualsalubrity. It is interesting to note here to show how some of the algæare diffused. I found here an artificial pond fed by a spring, andsubject to overflow from another pond in spring and winter. A stream ofliving water as large as one's arm (adult) feeds this artificial pond, still it was crowded with the Clathrocyotis æruginosa of some writersand the Polycoccus of Reinsch. How it got there has not yet beenexplained. 

The migration of the ague eastward is a matter of great interest; itis to be hoped that the localities may be searched carefully for yourplants, as I did in New Haven. 

In this connection I desire to say something about the presence of theGemiasmas in the Croton water. The record I have given of findingthe Gemiasma verdans is not a solitary instance. I did not find thegemiasmas in the Cochituate, nor generally in the drinking waters ofover thirty different municipalities or towns I have examined duringseveral years past. I have no difficulty in accounting for the presenceof the Gemiasmas in the Croton, as during the last summer I made studiesof the Gemiasma at Washington Heights, near 165th St. And 10th Ave. , N. Y. 

Plate VIII. Is a photograph of a drawing of some of the Gemiasmasprojected by the sun on the wall and sketched by the artist on the wall, putting the details in from microscopical specimens, viewed in theordinary way. This should make the subject of another observation. 

I visited this locality several times during August and October, 1881. Ifound an abundance of the saline incrustation of which you have spoken, and at the time of my first visit there was a little pond hole just eastof the point named that was in the act of drying up. Finally it driedcompletely up, and then the saline and green incrustations both wereabundant enough. The only species, however, I found of the ague plantswas the Gemiasma verdans. On two occasions of a visit with my pupils Idemonstrated the presence of the plants in the nasal excretions from mynostrils. I had been sneezing somewhat. 

There is one circumstance I would like to mention here: that was, thatwhen, for convenience' sake, my visits were made late in the day, Idid not find the plants abundant, still could always get enough todemonstrate their presence; but when my visits were timed so as to comein the early morning, when the dew was on, there was no difficultywhatever in finding multitudes of beautiful and well developed plants. 

To my mind this is a conclusive corroboration of your own statements inwhich you speak of the plants bursting, and being dissipated by theheat of the summer sun, and the disseminated spores accumulating inaggregations so as to form the white incrustation in connection withsaline bodies which you have so often pointed out. 

I also have repeated your experiments in relation to the collectionof the mud, turf, sods, etc. , and have known them to be carriedmany hundred miles off and identified. I have also found the littledepressions caused by the tread of cattle affording a fine nidus for theplants. You have only to scrape the minutest point off with a needle ortooth pick to find an abundance by examination. I have not been able toexplore many other sites, nor do I care, as I found all the materials Isought in the vicinity of New York. 

To this I must make one exception; I visited the Palisades last summerand examined the localities about Tarrytown. This is an elevatedlocation, but I found no Gemiasmas. This is not equivalent to sayingthere were none there. Indeed, I have only given you a mere outline ofmy work in this direction, as I have made it a practice to examine thesoil wherever I went, but as most of my observations have been conductedon non-malarious soils, and I did not find the plants, I have notthought it worth while to record all my observations of a negativecharacter. 

I now come to an important part of the corroborative observations, towit, the blood. 

I have found it as you predicted a matter of considerable difficulty tofind the mature forms of the Gemiasmas in the blood, but the spore formsof the vegetation I have no difficulty in finding. The spores haveappeared to me to be larger than the spores of other vegetations thatgrow in the blood. They are not capable of complete identificationunless they are cultivated to the full form. They are the so-calledbacteria of the writers of the day. They can be compared with the sporesof the vegetation found outside of the body in the swamps and bogs. 

You said that the plants are only found as a general rule in the bloodof old cases, or in the acute, well marked cases. The plants are so few, you said, that it was difficult to encounter them sometimes. So also ofthose who have had the ague badly and got well. 

Observation at Naval Hospital, N. Y. , Aug. , 1877. Examined with greatcare the blood of Donovan, who had had intermittent fever badly. Negative result. 

The same was the result of examining another case of typho-malarial(convalescent); though in this man's blood there were found someoval and sometimes round bodies like empty Gemiasmas, 1/1000 inch indiameter. But they had no well marked double outline. There were noforms found in the urine of this patient. In another case (Donovan, ) whosix months previous had had Panama fever, and had well nigh recovered, Ifound no spores or sporangia. 

Observations made at Washington, D. C. , Sept. , 1879. At this time Iexamined with clinical microscope the blood of eight to ten personsliving near the Congressional Cemetery and in the Arsenal grounds. I wassuccessful in finding the plants in the blood of five or more personswho were or had been suffering from the intermittent fever. 

In 1877, at the Naval Hospital, Chelsea, I accidentally came acrossthree well marked and well defined Gemiasmas in the blood of a marinewhom I was studying for another disease. I learned that he had hadintermittent fever not long before. 

Another positive case came to my notice in connection with micrographicwork the past summer. The artist was a physician residing in one of thesuburban cities of New York. I had demonstrated to him Gemiasma verdans, showed how to collect them from the soil in my boxes. And he had madeoutline drawings also, for the purposes of more perfectly completing hisdrawings. I gave him some of the Gemiasmas between a slide and cover, and also some of the earth containing the soil. He carried them home. Itso happened that a brother physician came to his house while he was atwork upon the drawings. My artist showed his friend the plants I hadcollected, then the plants he collected himself from the earth, and thenhe called his daughter, a young lady, and took a drop of blood fromher finger. The first specimen contained several of the Gemiasmas. Thedemonstration, coming after the previous demonstrations, carried aconviction that it otherwise would not have had. 

AGUE PLANTS IN THE URINE. 

I have found them in the urine of persons suffering or having sufferedfrom intermittent fever. 

When I was at the Naval Hospital in Brooklyn one of the accomplishedassistant surgeons, after I had showed him some plants in the urine, said he had often encountered them in the urine of ague cases, but didnot know their significance. I might multiply evidence, but think itunnecessary. I am not certain that my testimony will convince any onesave myself, but I know that I had rather have my present definite, positive belief based on this evidence, than to be floundering on doubtsand uncertainties. There is no doubt that the profession believe thatintermittents have a cause; but this belief has a vagueness which cannotbe represented by drawings or photograph. Since I have photographed theGemiasma, and studied their biology, I feel like holding on to yourdicta until upset by something more than words. 

In relation to the belief that no Algæ are parasitic, I would state onFeb. 9, 1878, I examined the spleen of a decapitated speckled turtlewith Professor Reinsch. We found various sized red corpuscles in theblood in various stages of formation; also filaments of a green Algatraversing the spleen, which my associate, a specialist in Algology, pronounced one of the Oscillatoriaceæ. These were demonstrated in yourown observations made years ago. They show that Algæ are parasitic inthe living spleen of healthy turtles. 

This leads to the remark that all parasitic growths are not nocent. Iunderstand you take the same position. Prof. Reinsch has published awork in Latin, "Contributiones ad Algologiam, " Leipsic, 1874, in whichhe gives a large number of drawings and descriptions of Algæ, many ofthem entophytic parasites on other animals or Algæ. Many of these hesaid were innocent guests of their host, but many guest plants weredeath to their host. This is for the benefit of those who say that theGemiasmas are innocent plants and do no harm. All plants, phanerogamsor cryptogams, can be divided into nocent or innocent, etc. , etc. Iam willing to change my position on better evidence than yours beingsubmitted, but till then call me an indorser of your work as to thecause and treatment of ague. 

Respectfully, yours, ------

There are quite a number of others who have been over my ground, but theabove must suffice here. 

[Illustration: PLATE X. --EXPLANATION OF FIGURES. --1, Spore with thicklaminated covering, constant colorless contents, and dark nucleus. B, Part of the wall of cell highly magnified, 0. 022 millimeter inthickness. 2, Smaller spore with verruculous covering. 3, Spore withpunctulated covering. 4, The same. 5, Minute spores with blue-greenishcolored contents, 0. 0021 millimeter in diameter. 6, Larger form of 5. 7, Transparent spherical spore, contents distinctly refracting the light, 0. 022 millimeter in diameter. 8, Chroococcoid minute cells, withtransparent, colorless covering, 0. 0041 millimeter in diameter. 9, Biciliated zoospore. 10, Plant of the Gemiasma rubra, thallus on bothends attenuated, composed of seven cells of unequal size. 11, Anothercomplete plant of rectangular shape composed of regularly attachedcells. 12, Another complete, irregularly shaped and arranged plant. 13, Another plant, one end with incrassated and regularly arranged cells. 14, Another elliptical shaped plant, the covering on one end attenuatedinto a long appendix. 15, Three celled plant. 16, Five celled plant. 10-16 magnified 440/1. ]

I wish to conclude this paper by alluding to some publishedinvestigations into the cause of ague, which are interesting, and whichI welcome and am thankful for, because all I ask is investigations--notwords without investigations. 

The first the Bartlett following:

Dr. John Bartlett is a gentleman of Chicago, of good standing in theprofession. In January, 1874, he published in the _Chicago MedicalJournal_ a paper on a marsh plant from the Mississippi ague bottoms, supposed to be kindred to the Gemiasmas. In a consideration of itsgenetic relations to malarious disease, he states that at Keokuk, Iowa, in 1871, near the great ague bottoms of the Mississippi, with Dr. J. P. Safford, he procured a sod containing plants that were as large as rapeseeds. He sent specimens of the plants to distinguished botanists, amongthem M. C. Cook, of London, England. Nothing came of these efforts. 

2. In August, 1873, Dr. B. Visited Riverside, near Chicago, to hunt upthe ague plants. Found none, and also that the ague had existed therefrom 1871. 

3. Lamonot, a town on the Illinois and Michigan Canal, was next visited. A noted ague district. No plants were found, and only two cases ofague, one of foreign origin. Dr. B. Here speaks of these plants of Dr. Safford's as causing ague and being different from the Gemiasmas. But hegives no evidence that Safford's plants have been detected in the humanhabitat. In justice to myself I would like to see this evidence beforegiving him the place of precedence. 

4. Dr. B. , Sept. 1, 1873, requested Dr. Safford to search for his plantsat East Keokuk. Very few plants and no ague were found where they bothwere rife in 1871. 

5. Later, Sept. 15, 1873, ague was extremely prevalent at East Keokuk, Iowa, where two weeks before no plants were found; they existed morenumerously than in 1871. 

6. Dr. B. Traced five cases of ague, in connection with Dr. Safford'splants found in a cesspool of water in a cellar 100 feet distant. It isdescribed as a plant to be studied with a power of 200 diameters, andconsisting of a body and root. The root is a globe with a central cavitylined with a white layer, and outside of these a layer of green cells. Diameter of largest plant, one-quarter inch. Cavity of plant filled withmolecular liquid. Root is above six inches in length, Dr. B. Found thewhite incrustation; he secured the spores by exposing slides at nightover the malarious soil resembling the Gemiasmas. He speaks of findingague plants in the blood, one-fifteen-hundredth of an inch in diameter, of ague patients. He found them also in his own blood associated withthe symptoms of remittent fever, quinine always diminishing or removingthe threatening symptoms. Professors Babcock and Munroe, of Chicago, call the plants either the Hydrogastrum of Rabenhorst, or the Botrydiumof the Micrographic Dictionary, the crystalline acicular bodies beingdeemed parasitic. Dr. B. Deserves great credit for his honest andcareful work and for his valuable paper. Such efforts are ever worthy ofrespect. 

There is no report of the full development found in the urine, sputa, and sweat. Again, Dr. B. Or Dr. Safford did not communicate the diseaseto unprotected persons by exposure. While then I feel satisfied that theGemiasmas produce ague, it is by no means proved that no other cryptogammay not produce malaria. I observed the plants Dr. B. Described, buteliminated them from my account. I hope Dr. B. Will pursue this subjectfarther, as the field is very large and the observers are few. 

When my facts are upset, I then surrender. 

"NOTES ON MARSH MIASM (LIMNOPHYSALIS HYALINA). BY ABR. FREDRIK EKLUND, M. D. , STOCKHOLM, SWEDEN, PHYSICIAN OF THE FIRST CLASS IN THE SWEDISHROYAL NAVY. 

[Footnote: Translated from the _Archives de la Medecine Navale_, vol. Xxx. , no. 7, July, 1878, by A. Sibley Campbell, M. D. , Augusta, Ga. ]

Before giving a succinct account of the discovery of paludal miasma andof its natural history, I ought in the first place to state that Ihave not had the opportunity of reading or studying the great originaltreatise of Professor Salisbury. I am acquainted with it only through aresume published in the _American Journal of the Medical Sciences_for the year 1866, new series, vol. Li. P. 51. At the beginning of myinvestigations I was engaged in a microscopic examination of the waterand mud of swampy shores and of the marshes, also with a comparison oftheir microphytes with those which might exist in the urine of patientsaffected with intermittent fevers. Nearly three months passed withoutmy being able to find the least agreement, the least connection. Havinglost nearly all hope of being able to attain the end which I hadproposed, I took some of the slime from the marshes and from the massesof kelp and Confervæ from the sea shores, where intermittent fevers areendemic, and placed them in saucers under the ordinary glass desiccatorsexposed on a balcony, open for twenty-four hours, the most of the timeunder the action of the burning rays of the sun. With the evaporatedwater deposited within the desiccators, I proceeded to an examination, drop by drop. I at length found that which I had sought so long, butalways in vain. 

The parasite of intermittent fever, which I have termed Limnophysalishyalina, and which has been observed before me by Drs. J. Lemaire andGratiolet (_Comptes Rendus Hebdomadaires de l'Academie des Sciences_, Paris, 1867, pp. 317 and 318) and B. Cauvet (_Archives de MedecineNavale_, November, 1876), is a fungus which is developed directlyfrom the mycelium, each individual of which possesses one or severalfilaments, which are simple or dichotomous, with double outlines, extremely fine, plainly marked, hyaline, and pointed. Under favorableconditions, that is, with moisture, heat, and the presence of vegetablematter in decomposition, the filaments of mycelium increase in length. From these long filaments springs the fungus. The sporangia, or moreexactly the conidia, are composed of unilocular vesicles, perfectlycolorless and transparent, which generally rise from one or both sidesof the filaments of the mycelium, beginning as from little buds or eyes;very often several (two to three) sporangia occur placed one upon theother, at least on one side of the mycelium. 

With a linear magnitude of 480, the sporangia have a transverse diameterof one to five millimeters, or a little more in the larger specimens. The filaments of mycelium, under the same magnitude, appear exceedinglythin and finer than a hair. The shape of the conidia, though presentingsome varieties, is, notwithstanding, always perfectly characteristic. Sometimes they resemble in appearance the segments of a semicircle moreor less great, sometimes the wings of butterflies, double or single. Itis only exceptionally that their form is so irregular. 

Again, when young, they are perfectly colorless and transparent;sometimes they are of a beautiful violet or blue color (mykianthininmykocyanin). Upon this variety of the Limnophysalis hyalina depends thevomiting of blue matters observed by Dr. John Sullivan, at Havana, inpatients affected with pernicious intermittent fever (algid and comatoseform). In the perfectly mature sporangia, the sporidia have a dark browncolor (mykophaein). From the sporidia, the Italian physicians, Lanzi andPerrigi, in the course of their attempts at its cultivation, have seenproduced the Monilia penicinata friesii, which is, consequently, thesecond generation of the Limnophysalis hyalina, in which alternategeneration takes place, admitting that their observations may beverified. The sporangia are never spherical, but always flat. Whenthey are perfectly developed, they are distinctly separated from theirfilament of mycelium by a septum--that is to say, by limiting linesplainly marked. It is not rare, however, to see the individual sporangiaperfectly isolated and disembarrassed of their filament of myceliumfloating in the water. It seems to me very probable that these isolatedsporangia are identical with the hyaline coagula so accurately describedby Frerichs, who has observed them in the blood of patients dying ofintermittent fevers. But if two sporangia are observed with their basescoherent without intermediary filaments of mycelium, it seems to meprobable that the reproduction has taken place through the union, whichhappens in the following manner: Two filaments of mycelium becomejuxtaposed; after which the filaments of mycelium disappear in thesporangia newly formed, which by this same metamorphosis are deprived ofthe faculty of reproducing themselves through the filaments of mycliumof which they are deprived. The smallest portion of a filamentof mycelium evidently possesses the faculty of producing the newindividuals. 

It is unquestionable that the Limnophysalis hyalina enter into the bloodeither by the bronchial mucous membrane, by the surface of the pulmonaryvesicles, or by the mucous membrane of the intestinal canal, most often, no doubt, by the last, with the ingested water; this introduction isaided by the force of suction and pressure, which facilitates theirabsorption. It develops in the glands of Lieberkuhn, and multipliesitself; after which the individuals, as soon as they are formed, aredrawn out and carried away in the blood of the circulation. 

The Limnophysalis hyalina is, in short, a solid body, of an extremelevity, and endowed with a most delicate organization. It is not amiasm, in the common signification of the term; it does not carry withit any poison; it is not vegetable matter in decomposition, but itflourishes by preference amid the last. 

In regard to other circumstances relative to the presence of thisfungus, there are, above all, two remarkable facts, namely, its propertyof adhering to surfaces as perfectly polished as that of a mirror, andits power of resistance against the reagents, if we except the causticalkalies and the concentrated mineral acids. This power of resisting theordinary reagents explains in a plausible manner why the fungus is notdestroyed by the digestive process in the stomach, where, however, theacid reaction of the gastric juice probably arrests its development--isthat of the schistomycetes in general--and keeps it in a state oftemporary inactivity. This property of adhering to smooth surfacesexplains perhaps the power of the Eucalyptus globulus in arresting theprogress of paludal miasm (?). But it is evident that other trees, shrubs, and plants of resinous or balsamic foliage, as, for example, thePopulus balsamifera, Cannabis sativa, Pinus silvestris, Pinus abies, Juniperus communis, have equally, with us, the same faculty; they arefavorable also for the drying of the soil, and the more completely, astheir roots are spreading, more extended, and more ramified. 

In order to demonstrate the presence of the limnophysalis in the bloodof patients affected with intermittent fever during the febrile stage, properly speaking, it appeared necessary for me to dilute the blood ofpatients with a solution of nitrate of potassa, having at 37. 5°C. Thesame specific gravity as the serum of the blood. With capillary tubes ofglass, a little dilated toward the middle, of the same shape and size asthose which are used in collecting vaccine lymph, I took up a littleof the solution of nitrate of potassa above indicated. After this Iintroduced the point of an ordinary inoculating needle under the skin, especially in the splenic region, where I ruptured some of the smallestblood-vessels of the subcutaneous cellular tissue. I collected someof the blood which flowed out or was forced out by pressure, in thecapillary tubes just described, containing a solution of potassa;after which I melted the ends with the flame of a candle. With all theintermittent fever patients whose blood I have collected and dilutedduring the febrile stage, properly speaking, I have constantly succeededin finding the Limnophysalis hyalina in the blood by microscopicexamination. 

It is only necessary for me to mention here that it is of the highestimportance to be able to demonstrate the presence of fungus in the bloodof the circulation and in the urine of patients in whom the diagnosisis doubtful. The presence of the Limnophysalis hyalina in the urineindicates that the patient is liable to a relapse, and that hisintermittent fever is not cured, which is important in a prognostic andtherapeutic point of view. 

When the question is to prevent the propagation of intermittent fevers, it is evident that it should be remembered that the Limnophysalishyalina enters into the blood by the mucous membrane of the organs ofrespiration, of digestion, and the surface of the pulmonary vesicles. Wehave also to consider the soil, and the water that is used for drinking. 

In regard to the soil, several circumstances are very worthy ofattention. It is desirable, not only to lower as much as possible thelevel of the subterranean water (grunawassen) by pipes of deep drainage, the cleansing, and if there is reason, the enlargement (J. Ory) ofthe capacity of the water collectors, besides covering and keeping inperfect repair the principal ditches in all the secondary valleys torender the lands wholesome, but also to completely drain the ground, diverting the rain water and cultivating the land, in the cultivation ofwhich those trees, shrubs, and plants should be selected which thrivethe most on marshy grounds and on the shores and paludal coasts of thesea, and which have their roots most speading and most ramified. Someof the ordinary grasses are also quite appropriate, but crops of thecereals, which are obtained after a suitable reformation of marshylands, yield a much better return. After the soil in the neighborhood ofthe dwellings has been drained and cultivated with care, and in a moresystematic manner than at present, the bottoms of the cellars should bepurified as well as the foundations of the walls and of the houses. 

The water intended for drinking, which contains the Limnophysalishyalina, should be freed from the fungus by a vigorous filtration. But, as it is known, the filtering beds of the basins in the water conduitsare soon covered with a thick coating of confervæ, and the Limnophysalishyalina then extends from the deepest portions of the filtering bedsinto the filtered water subjacent. It is for this reason that it isabsolutely necessary to renew so often the filtering beds of the waterconduits, and, at all events, before they have become coated with athick layer of confervæ. The disappearance of intermittent fevers willtestify to the utility of these measures. It is for a similar reasonthat wooden barrels are so injurious for equipages. When the wood hasbegun to decay by the contact of the impure water, the filaments ofmycelium of the Limnophysalis hyalina penetrate into the decayed wood, which becomes a fertile soil for the intermittent fever fungi. 

The employment for the preparation of mortar of water not filtered, orof foul, muddy sand which contains the Limnophysalis hyalina, explainshow intermittent fevers may proceed from the walls of houses. Thisarises also from the pasting of wall-paper with flour paste preparedwith water which contains an abundance of the fungi of intermittentfever. 

The miasm in the latter case is therefore endoecic, or more exactlyentoichic. With us the propagation of intermittent fever has beenobserved in persons occupying rooms scoured with unfiltered watercontaining the Limnophysalis hyalina in great quantity. 

The following imperial ordinance was published on the 25th of March, 1877, by the chief of admiralty of the German marine. It has for itsobject the prevention and eradication of infectious diseases:

"In those places where infectious diseases, according to experience, areprevalent and unusually severe and frequent, it is necessary to abstainas much as possible from the employment of water taken from without theship for cleansing said vessel, and also for washing out the hold whenthe water of the sea or of a river, in the judgment of the commander ofa vessel, confirmed by the statement of the physician, is shown to besurcharged with organic matter liable to putrefaction. With this end inview, if you are unable to send elsewhere for suitable water, you mustmake use of good and fresh water, but with the greatest economy. In thatevent the purification of the hold must be accomplished by mechanicalmeans or by disinfectants. "

"As I have demonstrated by my investigations that in the distillationof paludal water, and that from the marshy shores of the sea, theLimnophysalis hyalina, which is impalpable, is carried away and may bedetected again after the distillation, it must be insisted that thewater intended to be used for drinking on shipboard shall be carefullyfiltered before and after its distillation. "

The Klebs-Tommasi and Dr. Sternberg's report, as summarized in theSupplement No. 14, National Board of Health Bulletin, Washington, D. C. , July 18, I would cordially recommend to all students of this subject. 

I welcome these observers into the field. Nothing but good can come fromsuch careful and accurate observations into the cause of disease. Formyself I am ready to say that it may be that the Roman gentlemen havebit on the cause of the Roman fever, which is of such a pernicious type. I do not see how I can judge, as I never investigated the Roman fever;still, while giving them all due credit, and treating them with respect, in order to put myself right I may say that I have long ago ceased toregard all the bacilli, micrococci, and bacteria, etc. , as ultimateforms of animal or vegetable life. I look upon them as simply theembryos of mature forms, which are capable of propagating themselvesin this embryonal state. I have observed these forms in many diseasedconditions; many of them in one disease are nothing but the vinegaryeast developing, away from the air, in the blood where the fulldevelopment of the plant is not apt to be found. In diphtheria Ideveloped the bacteria to the full form--the Mucor malignans. So in thestudy of ague, for the vegetation which seems to me to be connected withague, I look to the fully developed sporangias as the true plant. 

Again, I think that crucial experiments should be made on man for hisdiseases as far as it is possible. Rabbits, on which the experimentswere made, for example, are of a different organization and food thanman, and bear tests differently. While there are so many human beingssubject to ague, it seems to me they should be the subjects on whom thecrucial tests are to be made, as I did in my labors. 

As far as I can see, Dr. Sternberg's inquiries tend to disprove theRoman experiments, and as he does not offer anything positive as acause of ague, I can only express the hope that he will continue hisinvestigations with zeal and earnestness, and that he will producesomething positive and tangible in his labors in so interesting andimportant a field. 

I would then that all would join hands in settling the cause of thisdisease; and while I do not expect that all will agree with me, still, Ishall respect others' opinions, and so long as I keep close to my factsI shall hope my views, based on my facts, will not be treated withdisrespect. 

APPENDIX. 

Gemiasma verdans and Gemiasma rubra collected Sept. 10, 1882, onWashington Heights, near High Bridge. The illustrations show the mannerin which the mature plants discharge their contents. 

Plate VIII. A, B, and C represent very large plants of the Gemiasmaverdans. A represents a mature plant. B represents the same plant, discharging its spores and spermatia through a small opening in the cellwalls. The discharge is quite rapid but not continuous, being spasmodic, as if caused by intermittent contractions in the cell walls. Thedischarge begins suddenly and with considerable force--a sort ofexplosion which projects a portion of the contents rapidly and to quitea little distance. This goes on for a few seconds, and then the cell isat rest for a few seconds, when the contractions and explosions beginagain and go on as before. Under ordinary conditions it takes a plantfrom half an hour to an hour to deliver itself. It is about two-thirdsemptied. C represents the mature plant, entirely emptied of its sporecontents, there remaining inside only a few actively moving spermatia, which are slowly escaping. The spermatia differ from the spores andyoung plants in being smaller, and of possessing the power of moving andtumbling about rapidly, while the spores of young plants are largerand quiescent. D, E, F, and G represent mature plants belonging to theGemiasma rubra. D represents a ripe plant, filled with spores, embryonicplants, and spermatia. E represents a ripe plant in the act ofdischarging its contents, it being about half emptied. F representsa ripe plant after its spore and embryonic plant contents are alldischarged, leaving behind only a few actively moving spermatia, whichare slowly escaping. G represents the emptied plant in a quiescentstate. 

Figs. A, B, C represent an unusually large variety of the Gemiasmaverdans. This species is usually about the size of the rubra. Thislarge variety was found on the upper part of New York Island, near HighBridge, in a natural depression where the water stands most of theyear, except in July, August, and September, when it becomes an areaof drying, cracked mud two hundred feet across. As the mud dries theseplants develop in great profusion, giving an appearance to the surfaceas if covered thickly with brick dust. 

These depressions and swaily places, holding water part of the year, andbecoming dry during the malarial season, can be easily dried by meansof covered drains, and grassed or sodded over, when they will cease togrow; this vegetation and ague in such localities will disappear. 

The malarial vegetations begin to develop moderately in July, but do notspring forth abundantly enough to do much damage till about the middleof August, when they in ague localities spring into existence in vastmultitudes, and continue to develop in great profusion till frost comes. 

 * * * * *

ANALYSIS OF THE MALARIA PLANT (GEMIASMA RUBRA). 

By Prof Paulus F. Reinsch. 

Author Algæ of France, 1866; Latest Observations on Algology, 1867;Chemical Investigation of the Connections of the Lias and JuraFormations, 1859; Chemical Investigation of the Viscum Album, 1860;Contributions to Algology and Fungology, 1874-75, vol. I. ; NewInvestigation of the Microscopic Structure of Pit Coal, 1881;Micrographic Photographs of the Structure and Composition of Pit Coal, 1888. 

Dr. Cutter writes me September 28, 1882: "My dear Professor: By thismail I send you a specimen of the Gemiasma rubra of Salisbury, describedin 1862, as found in bogs, mud holes, and marshes of ague districts, inthe air suspended at night, in the sputa, blood, and urine, and onthe skin of persons suffering with ague. It is regarded as one of thePalmellaceæ. This rubra is found in the more malignant and fatal typesof the disease. I have found it in all the habitats described by Dr. Salisbury. Both he and myself would like you to examine and hear whatyou have to say about it. "

The substance of clayish soil contains, besides fragments of shells oflarger diatoms (Suriella synhedra), shells of Navicula minutissima, Pinnularia viridis. Spores belonging to various cryptogams. 

1. Spherical transparent spores with laminated covering and darknucleus--0. 022 millimeter in diameter. 

2. Spherical spores with thick covering of granulated surface. 

3. Spherical spores with punctulated surface--0. 007 millimeter indiameter. 

4. Very minute, transparent, bluish-greenish colored spores, with thincovering and finely granulated contents--0. 006 millimeter in diameter. 

5. Chroococcoid cells with two larger nuclei--0. 0031 millimeter indiameter. Sometimes biciliated minute cells are found; without any doubtthey are zoospores derived from any algoid or fungoid species. 

I cannot say whether there exists any genetic connection between thesevarious sorts of spores. It seems to me that probably numbers 1-4represent resting states of the hyphomycetes. 

No. 5 represents one and two celled states of chroococcus species belongto Chroococcus minutus. 

The crust of the clayish earth is covered with a reddish brown coveringof about half a millimeter in thickness. This covering proves to becomposed, under the microscope, of cellular filaments and various shapedbodies of various composition. They are made up of cells with denselyand coarsely granulated reddish colored contents--shape, size, andcomposition are very variable, as shown in the figures. _The cellularbodies make up the essential organic part of the clayish substance, and, without any doubt, if anything of the organic compounds of the substanceis in genetical connection with the disease, these bodies would havethis role_. The structure and coloration of cell contents exhibit theclosest alliance to the characteristics of the division of Chroolepideæand of this small division of Chlorophyllaceous Algæ, nearest toGongrosira--a genus whose five to six species are inhabitants of freshwater, mostly attached to various minute aquatic Algæ and mosses. Eachcell of all the plants of this genus produces a large number of mobilecells--zoospores. 

Fig. 9 represents very probably one zoospore developed from these plantsas figured from 10 to 16. 

 * * * * *

CARBON. 

M. Berthelot, in the _Journal de Pharmacie et de Chimie_ for March, states that from peculiar physical relations he is led to suspect thatthe true element carbon is unknown, and that diamond and graphite aresubstances of a different order. Elementary carbon ought to be gaseousat the ordinary temperature, and the various kinds of carbon whichoccur in nature are in reality polymerized products of the true elementcarbon. Spectrum analysis is thought to confirm this view; and it issupposed the second spectrum seen in a Geissler tube belongs to gaseouscarbon. This spectrum, which has been recognized along with that ofhydrogen in the light of the tails of comets, indicates a carbide, probably acetylene. 

 * * * * *

CANNED MEATS. 

By P. CARLES. 

When tinned iron serves for containing alimentary matters, it isessential that the tin employed should be free from lead. The lattermetal is rapidly oxidized on the surface and is dissolved in this formin the neutral acids of vegetables, meat, etc. The most exact methodof demonstrating the presence of lead consists in treating thealloy--so-called tin--with _aqua regia_ containing relatively littlenitric acid. The whole dissolves; the excess of acid is driven off byevaporation at a boiling heat, and the residue, diluted with water, issaturated with hydrogen sulphide. The iron remains in solution, whilethe mixed lead and tin sulphides precipitated are allowed to digest fora long time in an alkaline sulphide. The tin sulphide only dissolves; itis filtered off and converted into stannic acid, while the lead sulphideis transformed into sulphate and weighed as such. 

 * * * * *

NEW BLEACHING PROCESS, WITH REGENERATION OF THE BATHS USED. 

By MR. BONNEVILLE. 

To a cold solution containing 1 per cent. Of bromine, 1 per cent. Ofcaustic soda at 36° B. Is added, then the material, to be bleached isfirst wet and then immersed in this bath until completely decolorized. It is passed into a newly-acidulated bath, rinsed, and dried. After thebromine bath has been used up, it is regenerated by adding 1 per cent. Of sulphuric acid, which liberates the bromine. To the same bathcaustic soda is added, which regenerates the hypobromite of soda. Thehydrofluosilicic acid can be used, instead of the sulphuric acid, withgreater advantage. A bath used up can also be regenerated by means ofthe electric current. 

 * * * * *

DETECTION OF MAGENTA, ARCHIL, AND CUDBEAR IN WINE. 

These colors are not suitable for converting white wine into red, butthey can be used for giving wines a faint red tint, for darkening palered wines, and in making up a factitious bouquet essence, which is addedto red wines. The most suitable methods for the detection of magenta arethose given by Romei and Falieres-Ritter. If a wine colored with archiland one colored with cudbear are treated treated according to Romei'smethod, the former gives, with basic lead acetate, a blue, and thelatter a fine violet precipitate. The filtrate, if shaken up with amylicalcohol, gives it in either case a red color. A knowledge of this factis important, or it may be mistaken for magenta. The behavior of theamylic alcohol, thus colored red, with hydrochloric acid and ammonia ischaracteristic. If the red color is due to magenta, it is destroyed byboth these reagents, while hydrocholoric acid does not decolorize thesolutions of archil and cudbear, and ammonia turns their red color to apurple violet. If the wine is examined according to the Falieres-Rittermethod in presence of magenta, ether, when shaken up with the wine, previously rendered ammoniacal, remains colorless, while if archilor cudbear is present the ether is colored red. Wartha has made aconvenient modification in the Falieres-Ritter method by adding ammoniaand ether to the concentrated wine while still warm. If the red color ofthe wool is due to archil or cudbear, it is extracted by hydrochloricacid, which is colored red. Ammonia turns the color to a purple violet. König mixed 50 c. C. Wine with ammonia in slight excess, and places inthe mixture about one-half grm. Clean white woolen yarn. The whole isthen boiled in a flask until all the alcohol and the excess of ammoniaare driven off. The wool taken out of the liquid and purified by washingin water and wringing is moistened in a test-tube with pure potassalye at 10 per cent. It is carefully heated till the wool is completelydissolved, and the solution, when cold, is mixed first with half itsvolume of pure alcohol, upon which is carefully poured the same volumeof ether, and the whole is shaken. The stratum of ether decanted off ismixed in a test-tube with a drop of acetic acid. A red color appears ifthe slightest trace of magenta is present. The shaking must not be tooviolent, lest an emulsion should be formed. If the wine is colored witharchil, on prolonged heating, after the addition of ammonia, it isdecolorized. If it is then let cool and shaken a little, the red colorreturns. If the wool is taken out of the hot liquid after the red colorhas disappeared, and exposed to the air, it takes a red color. But ifit is quickly taken out of the liquid and at once washed, there remainsmerely a trace of color in the wool. If these precautions are observed, magenta can be distinguished from archil with certainty according toKönig's method. As the coloring-matter of archil is not precipitatedby baryta and magnesia, but changed to a purple, the baryta method, recommended by Pasteur, Balard, and Wurtz, and the magnesia test, areuseless. Magenta may in course of time be removed by the precipitatesformed in the wine. It is therefore necessary to test not merely theclear liquid, but the sediment, if any. --_Dr. B. Haas, in Budermann'sCentralblatt. --Analyst_. 

 * * * * *

PANAX VICTORIÆ. 

Panax Victoriæ is a compact and charming plant, which sends up numbersof stems from the bottom in place of continually growing upward and thusbecoming ungainly; it bears a profusion of elegantly curled, tasseled, and variegated foliage, very catching to the eye, and unlike any of itspredecessors. The other, P. Dumosum, is of similar habit, the foliagebeing crested and fringed after the manner of some of our rare crestedferns. --_The Gardeners' Chronicle_. 

[Illustration: PANAX VICTORIÆ. ]

 * * * * *

A NOTE ON SAP. 

[Footnote: Read at an evening meeting of the Pharmaceutical Society, London, April 4, 1883. ]

By Professor ATTFIELD, F. R. S. 

Beneath a white birch tree growing in my garden I noticed, yesterdayevening, a very wet place on the gravel path, the water of which wasobviously being fed by the cut extremity of a branch of the birch aboutan inch in diameter and some ten feet from the ground. I afterward foundthat exactly fifteen days ago circumstances rendered necessary theremoval of the portion of the branch which hung over the path, 4 or 5feet being still left on the tree. The water or sap was dropping fastfrom the branch, at the rate of sixteen large drops per minute, eachdrop twice or thrice the size of a "minim, " and neither catkins norleaves had yet expanded. I decided that some interest would attach to adetermination both of the rate of flow of the fluid and of its chemicalcomposition, especially at such a stage of the tree's life. 

A bottle was at once so suspended beneath the wound as to catch thewhole of the exuding sap. It caught nearly 5 fluid ounces between eightand nine o'clock. During the succeeding eleven hours of the night 44fluid ounces were collected, an average of 4 ounces per hour. From 8:15to 9:15 this morning, very nearly 7 ounces were obtained. From 9:15to 10:15, with bright sunshine, 8 ounces. From 10:15 until 8:15 thisevening the hourly record kept by my son Harvey shows that the amountduring that time has slowly diminished from 8 to a little below 7 ouncesper hour. Apparently the flow is faster in sunshine than in shade, andby day than by night. 

It would seem, therefore, that this slender tree, with a stem which atthe ground is only 7 inches in diameter, having a height of 39 feet, and before it has any expanded leaves from whose united surfaces largeamounts of water might evaporate, is able to draw from the ground about4 liters, or seven-eighths of a gallon of fluid every twenty-four hours. That at all events was the amount flowing from this open tap in itswater system. Even the topmost branches of the tree had not become, during the fifteen days, abnormally flaccid, so that, apparently, nodrainage of fluid from the upper portion of the tree had been takingplace. For a fortnight the tree apparently had been drawing, pumping, sucking--I know not what word to use--nearly a gallon of fluid dailyfrom the soil in the neigborhood of its roots. This soil had only anordinary degree of dampness. It was not wet, still less was there anyactually fluid water to be seen. Indeed, usually all the adjacent soilis of a dry kind, for we are on the plateau of a hill 265 feet above thesea, and the level of the local water reservoir into which our wells dipis about 80 feet below the surface. My gardener tells me that the treehas been "bleeding" at about the same rate for fourteen of the fifteendays, the first day the branch becoming only somewhat damp. During theearlier part of that time we had frosts at night, and sunshine, but withextremely cold winds, during the days. At one time the exuding sapgave, I am told by two different observers, icicles a foot long. A muchwarmer, almost summer, temperature has prevailed during the past threedays, and no wind. This morning the temperature of the sap as it escapedwas constant at 52° F. , while that of the surrounding air was varyingconsiderably. 

The collected sap was a clear, bright, water-like fluid. After a pinthad stood aside for twelve hours, there was the merest trace of asediment at the bottom of the vessel. The microscope showed this toconsist of parenchymatous cells, with here and there a group ofthe wheel-like or radiating cells which botanists, I think, termsphere-crystals. The sap was slightly heavier than water, in theproportion of 1, 005 to 1, 000. It had a faintly sweet taste and a veryslight aromatic odor. 

Chemical analysis showed that this sap consisted of 99 parts of purewater with 1 part of dissolved solid matter. Eleven-twelfths of thelatter were sugar. 

That the birch readily yields its sap when the wood is wounded is wellknown. Philipps, quoted by Sowerby, says:

 "Even afflictive birch, Cursed by unlettered youth, distills, A limpid current from her wounded bark, Profuse of nursing sap. "

And that birch sap contains sugar is known, the peasants of manycountries, especially Russia, being well acquainted with the art ofmaking birch wine by fermenting its saccharine juice. 

But I find no hourly or daily record of the amount of sugar-bearingsap which can be drawn from the birch, or from any tree, before ithas acquired its great digesting or rather developing and transpiringapparatus--its leaf system. And I do not know of any extended chemicalanalysis of sap either of the birch, or other tree. 

Besides sugar, which is present in this sap to the extent of 616grains--nearly an ounce and a half--per gallon, there are present amere trace of mucilage; no starch; no tannin; 3½ grains per gallonof ammoniacal salts yielding 10 per cent. Of nitrogen; 3 grains ofalbuminoid matter yielding 10 per cent. Of nitrogen; a distinct trace ofnitrites; 7. 4 grains of nitrates containing 17 per cent. Of nitrogen; nochlorides, or the merest trace; no sulphates; no sodium salts; a littleof potassium salts; much phosphate and organic salts of calcium; andsome similar magnesian compounds. These calcareous and magnesiansubstances yield an ash when the sap is evaporated to dryness and thesugar and other organic matter burnt away, the amount of this residualmatter being exactly 50 grains per gallon. The sap contained no peroxideof hydrogen. It was faintly if at all acid. It held in solution aferment capable of converting starch into sugar. Exposed to the air itsoon swarmed with bacteria, its sugar being changed to alcohol. 

A teaspoonful or two of, say, apple juice, and a tablespoonful of sugarput into a gallon of such rather hard well-water as we have in ourchalky district, would very fairly represent this specimen of the sap ofthe silver birch. Indeed, in the phraseology of a water-analyst, I maysay that the sap itself has 25 degrees of total, permanent hardness. 

How long the tree would continue to yield such a flow of sap I cannotsay; probably until the store of sugar it manufactured last summer tofeed its young buds this spring was exhausted. Even within twenty-fourhours the sugar has slightly diminished in proportion in the fluid. 

Whether or not this little note throws a single ray of light on the muchdebated question of the cause of the rise of sap in plants I must leaveto botanists to decide. I cannot hope that it does, for Julius Sachs, than whom no one appears to have more carefully considered the subject, says, at page 677 of the recently published English translation of histextbook of botany, that "although the movements of water in plants havebeen copiously investigated and discussed for nearly two hundred years, it is nevertheless still impossible to give a satisfactory and deductiveaccount of the mode of operation of these movements in detail. " Asa chemist and physicist myself, knowing something about capillaryattraction, exosmose, endosmose, atmospheric pressure, and gravitationgenerally, and the movements caused by chemical attraction, I am afraidI must concur in the opinion that we do not yet know the real ultimatecause or causes of the rise of sap in plants. 

Ashlands, Watford, Herts. 

 * * * * *

THE CROW. 

[Footnote: Abstract of a recent discussion before the Connecticut StateBoard of Agriculture. ]

Prof. W. A. Stearns, in a lecture upon the utility of birds inagriculture, stated that the few facts we do know regarding the matterhave been obtained more through the direct experience of those who havestumbled on the facts they relate than those who have made any specialstudy of the matter. One great difficulty has been that people lookedtoo far and studied too deeply for facts which were right before them. For instance, people are well acquainted with the fact that hawks, becoming bold, pounce down upon and carry off chickens from thehen-yards and eat them. How many are acquainted with the fact that inhard winters, when pressed for food, crows do this likewise? Butwhat does this signify? Simply that the crow regulates its food fromnecessity, not from choice. 

Now, carry this fact into operation in the spring into the cornfield. Doyou suppose that the crow, being hungry, and dropping into a field ofcorn wherein is abundance to satisfy his desires, stops, as many affirm, to pick out only those kernels which are affected with mildew, larva, orweevil? Does he instinctively know what corns, when three or four inchesbeneath the ground, are thus affected? Not a bit of it. To him, astrictly grain-feeding and not an insect-eating bird, the necessitytakes the place of the choice. He is hungry; the means of satisfying hishunger are at hand. He naturally drops down in the first cornfieldhe sees, calls all his neighbors to the feast, and then roots up andswallows all the kernels until he can hold no more. There is no doubtthe crow is a damage to the agriculturist. He preys upon the cornfieldand eats the corn indiscriminately, whether there are any insects ornot. That has been proved by dissection of stomach and crop. 

If corn can be protected by tarring, so that the crows will not eat it, they will prove a benefit by leaving the corn and picking up grubs inthe field. Where corn has been tarred, I have never known the crows totouch it. 

Mr. Sedgwick remarked that, in addition to destroying the corn crop, thecrow was also very destructive of the eggs of other birds. Last springI watched a pair of crows flying through an orchard, and in severalinstances saw them fly into birds' nests, take out the eggs, and then goon around the field. 

In answer to Mr. Hubbard, who claimed the crow would eat animal food inany form, and might not be rightly classified as a grain-eating bird, Prof. Stearns said the crow was thus classified by reason of thestructure of its crop being similar to that of the finches, theblackbird, the sparrows, and other seed-eating birds. 

[Illustration: THE AMERICAN CROW. ]

Mr. Wetherell said: Crows are greedy devourers of the white worm, whichsometimes destroys acres of grass. As a grub eater, the crow deservesmuch praise. The crow is the scavenger of the bird family, eatinganything and everything, whether it is sweet or carrion. The onlyquarrel I have with the crow is because it destroys the eggs and youngbirds. 

Mr. Lockwood described the experience of a neighbor who planted cornafter tarring it. This seemed to prevent the ravages of the crows untilthe second hoeing, when the corn was up some eighteen inches, at whichtime the crows came in and pulled nearly an acre clean. 

Crows, said Dr. Riggs, have no crop, like a great many carnivorousbirds. The passage leading from the mouth goes directly to the gizzard, something like the duck. The duck has no crop, yet the passage leadingfrom the mouth to the gizzard in the duck becomes considerably enlarged. In the crow there is no enlargement of this passage, and everythingpasses directly into the gizzard, where it is digested. 

Dr. Riggs had raised corn and watched the operations of the crows. Goingupon the field in less than a minute after the crows had left it, hefound they had pulled the corn, hill after hill, marching from one hillto the other. Not until the corn had become softened and had come upwould they molest it. In the fall they would come in droves on to afield of corn, where it is in stacks, pick out the corn from the husks, and put it into their gizzards. They raid robbins' nests and swallows'nests, devouring eggs and young birds. Yet crows are great scavengers. In the spring they get a great many insects and moths from the ground, and do good work in picking up those large white grubs with red headsthat work such destruction in some of our mowing fields. 

Mr. Pratt stated that he had used coal tar on his seed corn for five orsix years, and had never a spear pulled by the crows. Dr. Riggs neverhad known a crow to touch corn after it got to the second tier ofleaves. Mr. Lockwood said crows would sample a whole field of corn tofind corn not tarred. Mr. Pratt recommended to pour boiling water on thecorn before applying the tar. A large tablespoonful of tar will color apail of water. 

According to Dr. Riggs, the hot mixture with the corn must be stirredcontinually; if not, the life of the corn will be killed and germinationprevented. It may be poured on very hot, if the stirring is kept up andtoo much tar is not used. If the water is hot it will dissolve the tar, and as it is poured on it will coat every kernel of corn. If the wateris allowed to stand upon the corn any great length of time, the chit ofthe corn will be damaged. The liquid should be poured off and the cornallowed to cool immediately after a good stirring. 

Mr. Gold had known of crows pulling corn after the second hoeing, whenthe scare-crows had been removed from the field. The corn thus pulledhad reached pretty good size. This pulling must have been done fromsheer malice on the part of the crows. 

Mr. Ayer was inclined to befriend the crow. For five years he hadplanted from eight to twelve acres of corn each year and had not losttwenty hills by crows. He does not use tar, but does not allow himselfto go out of a newly-planted cornfield without first stretching a stringaround it on high poles and also providing a wind-mill with a littlerattle box on it to make a noise. With him this practice keeps the crowsaway. 

Mr. Goodwin thought crows were scavengers of the forests and did goodservice in destroying the worms, grubs, and insects that preyed uponour trees. He had raised some forty crops of corn, and whenever he hadthoroughly twined it at the time of planting, crows did not pull it up. In damp spots, during the wet time and after his twine was down, he hadknown crows to pull up corn that was seven or eight inches high. 

Respecting crows as insect eaters, Prof. Stearns admitted that they diddevour insects; he had seen them eat insects on pear trees. Tame crowsat his home had been watched while eating insects, yet a crow willeat corn a great deal quicker than he will eat insects. --_BostonCultivator_. 

 * * * * *

THE PRAYING MANTIS AND ITS ALLIES. 

On examining the strange forms shown in the accompanying engraving, manypersons would suppose they were looking at exotic insects. Although thisis true for many species of this group, which are indigenous to warmcountries, and reach at the most only the southern temperate zone, yetthere are certain of these insects that are beginning to be found inFrance, to the south of the Loire, and that are always too rare, since, being exclusively feeders on living prey, they prove useful aids to us. 

These insects belong among the orthoptera--an order including specieswhose transformations are less complete than in other groups, and whoselarval and pupal forms are very active, and closely resemble the imago. Two pairs of large wings characterize the adult state, the first pairof which are somewhat thickened to protect the broad, net-veined hinderpair, which fold up like a fan upon the abdomen. The hind legs are largeand adapted for leaping. 

The raptorial group called _Mantidæ_, which forms the subject of thisarticle, includes species that maybe easily recognized by their largesize, their enormous, spinous fore legs, which are adapted for seizingother insects, and from their devotional attitude when watching theirprey. 

These insects exhibit in general the phenomenon of mimicry, oradaptation for protection, through their color and form, some beinggreen, like the plants upon which they live, others yellowish orgrayish, and others brownish like dead leaves. 

In the best known species, _Mantis religiosa_, the head is triangular, the eyes large, the prothorax very long, and the body narrowed andlengthened; the anterior feet are armed with hooks and spines, and theshanks are capable of being doubled up on the under side of the thighs. When at rest it sits upon the four posterior legs, with the head andprothorax nearly erect, and the anterior feet folded backward. Thefemale insect attains a length of 54 millimeters, and the male only 40. 

The color is of a handsome green, sometimes yellow, or of a yellowishred. The insects are slow in their motions, waiting on the branches oftrees and shrubs for some other insect to pass within their reach, whenthey seize and hold it with the anterior feet, and tear it to pieces. They are very voracious, and sometimes prey upon each other. Their eggsare deposited in two long rows, protected by a parchment-like envelope, and attached to the stalk of a plant. The nymph is as voracious as theperfect insect, from which it differs principally in the less developedwings. 

The devotional attitude of these insects when watching for theirprey--their fore legs being elevated and joined in a supplicatingmanner--has given them in English the popular names of "soothsayer, ""prophet, " and "praying mantis, " in French, "prie-Dieu, " in Portuguese, "louva-Deos, " etc. According to Sparmann, the Nubians and Hottentotsregard mantides as tutelary divinities, and worship them as such. Amonkish legend tells us that Saint Francis Xavier, having perceived amantis holding its legs toward heaven, ordered it to sing the praises ofGod, when immediately the insect struck up one of the most exemplary ofcanticles! Pison, in his "Natural History of the East Indies, " makes useof the word _Vates_ (divine) to designate these insects, and speaks ofthat superstition, common to both Christians and heathens, that assignsto them the gifts of prophecy and divination. The habit that the mantishas of first stretching out one fore leg, and then the other, and ofpreserving such a position for some little time, has also led to thebelief among the illiterate that it is in the act, in such cases, ofpointing out the road to the passer by. 

[Illustration: MANTIDES AND EMPUSÆ]

The old naturalist, Moufet, in his _Theatrum Insectorum_ (London, 1634), says of the praying mantis (_M. Religiosa_) that it is reported sodivine that if a child asks his way of it, it will show him the rightroad by stretching out its leg, and that it will rarely or never deceivehim. 

This group of insects is most abundant in the tropical regions ofAfrica, South America, and India, but some species are found in thewarmer parts of North America, Europe, and Australia. The Americanspecies is the "race-horse" (_M. Carolina_), and occurs in the Southernand Western States. Burmeister says that _M. Argentina_, of BuenosAyres, seizes and eats small birds. 

The genera allied to _Mantis--Vates, Empusa, Harpax_, and_Schizocephala_--occur in the tropics. The genus _Eremophila_ inhabitsthe deserts of Northern Africa, where it resembles the sand in color. 

The species shown in the engraving (which we borrow from _La Nature_)inhabit France. 

 * * * * *

MAY-FLIES. 

There are usually found in the month of June, especially near water, certain insects that are called Ephemera, and which long ago acquiredtrue celebrity, and furnished material for comparison to poets andphilosophers. Indeed, in the adult state they live but one day, a factthat has given them their name. They appear for a few hours, flutteringabout in the rays of a sun whose setting they are not to see, as theylive during the space of a single twilight only. These insects havevery short antennæ, an imperfect mouth incapable of taking food, anddelicate, gauze like wings, the posterior ones of which are alwayssmall, or even rudimentary or wanting. Their legs are very delicate--theanterior ones very long--and their abdomen terminates in two or threelong articulated filaments. One character, which is unique amonginsects, is peculiar to Ephemerids; the adults issuing from the pupalenvelope undergo still another moult in divesting themselves of a thinpellicle that covers the body, wings, and other appendages. This is whatis called the _subimago_, and precedes the imago or perfect state of theinsect. The short life of adult May-flies is, with most of them, passedin a continual state of agitation. They are seen rising vertically ina straight line, their long fore-legs stretched out like antennæ, andserving to balance the posterior part of the body and the filamentsof the abdomen during flight. On reaching a certain height they allowthemselves to descend, stretching out while doing so their long wingsand tail, which then serve as a parachute. Then a rapid working of theseorgans suddenly changes the direction of the motion, and they begin toascend again. Coupling takes place during these aerial dances. Soonafterward the females approach the surface of the water and lay thereintheir eggs, spreading them out the while with the caudal filaments, orelse depositing them all together in one mass that falls to the bottom. 

These insects seek the light, and are attracted by an artificial one, describing concentric circles around it and finally falling into it andbeing burnt up. Their bodies on falling into the water constitute a foodwhich is eagerly sought by fishes, and which is made use of by fishermenas a bait. 

But the above is not the only state of Ephemerids, for their entireexistence really lasts a year. Linnæus has thus summed up the total lifeof these little creatures: "The larvæ swim in water; and, in becomingwinged insects, have only the shortest kind of joy, for they oftencelebrate in a single day their wedding, parturition, and funeralobsequies. " The eggs, in fact, give birth to more or less elongatedlarvæ, which are always provided with three filaments at the end ofthe abdomen, and which breathe the oxygen dissolved in the water bytracheo-branchiæ along the sides of the body. They are carnivorous, andlive on small animal prey. The most recent authors who have studiedthem are Mr. Eaton, in England, and Mr. Vayssiere, of the Faculte desSciences, at Marseilles. 

_A propos_ of the larvæ of Ephemera or May-flies, we must speak of oneof the entomological rarities of France, the nature and zoological placeof which it has taken more than a century to demonstrate. Geoffroy, theold historian of the insects of the vicinity of Paris, was the first tofind in the waters of the Seine a small animal resembling one of theDaphnids. This animal has six short and slender thoracic legs, whichterminate in a hook and are borne on the under side of the cephalicshield. This latter is provided above with two slender six-jointedantennæ, two very large faceted eyes at the side, and three ocelliforming a triangle. The large thoraceo-abdominal shield is hollowed outbehind into two movable valves which cover the first five segments ofthe abdomen (Fig. 1). The last four segments, of decreasing breadth, are retractile beneath the carapax, as is also the broad plume thatterminates them, and which is formed of three short, transparent, andelegantly ciliated bristles. These are the locomotive organs of theanimal, whose total length, with the segments of the tail expanded, doesnot exceed seven to eight millimeters. The animal is found in runningwaters, at a depth of from half a meter to a meter and a half. It hidesunder stones of all sizes, and, as soon as it is touched, its first careis to fix itself by the breast to their rough surface, and then to swimoff to a more quiet place. It fastens itself so firmly to the stone thatit is necessary to pass a thin knife-blade under it in order to detachit. 

[Illustration: FIG. 1. --LARVA OF MAY FLY. (Magnified 12 times. )]

Geoffroy, because of the two large eyes, and without paying attention tothe ocelli, named this larva the "feather-tailed binocle. " C. Dumeril, in 1876, found it again in pools that formed after rains, and named thecreature (which is of a bluish color passing to red) the "pisciformbinocle. " Since then, this larva has been found in the Seine atPoint-du-Jour, Bas-Meudon, and between Epone and Mantes. Latreille, in 1832, decided it to be a crustacean, and named it _Prosopistomafoliaceum_. In September, 1868, the animal was found at Toulouse by Dr. E. Joly in the nearly dry Garonne. Finally, in 1880, Mr. Vayssiere metwith it in abundance in the Rhone, near Avignon. 

The abnormal existence of a six-legged crustacean occupied theattention of naturalists considerably. In 1869, Messrs. N. And E. Jolydemonstrated that the famous "feather-tailed binocle" was the larva ofan insect. They found in its mouth the buccal pieces of the Neuroptera, and, under the carapax, five pairs of branchial tufts attached to thesegments that are invisible outwardly. Inside the animal were foundtracheæ, the digestic tube of an insect, and malpighian canals. Finally, in June, 1880, Mr. Vayssière was enabled to establish the factdefinitely that the insect belonged among the Ephemerids. Two of thelarvae that he raised in water became, from yellowish, gradually brown. Then they crawled up a stone partially out of water, the carapaxgradually split, and the adults readily issued therefrom--the headfirst, then the legs, and finally the abdomen. At the same time, thewings, which were in three folds in the direction of their length, spread out in their definite form (Fig. 2). The insects finally flewaway to alight at a distance from the water. The wings of the insect, which are of an iron gray, are covered with a down of fine hairs. Theposterior ones soon disappear. 

[Illustration: FIG. 2. --MAY-FLY (adult magnified 14 times). ]

Perhaps the subimago in this genus of Ephemerids, as in certain others, is the permanent aerial state of the female. --_La Nature_. 

 * * * * *

Connecticut is rapidly advancing in the cultivation of oysters. About90, 000 acres are now planted, and thirty steamers and many sailingvessels are engaged in the trade. 

 * * * * *

THE COLOR OF WATER. 

It is well known that the water of different lakes and rivers differs incolor. The Mediterranean Sea is indigo blue, the ocean sky blue, LakeGeneva is azure, while the Lake of the Four Forest Cantons and LakeConstance, in Switzerland, as well as the river Rhine, are chrome green, and Kloenthaler Lake is grass green. 

Tyndall thought that the blue color of water had a similar cause asthe blue color of the air, being blue by reflected light and red bytransmitted light. W. Spring has recently communicated to the BelgianAcademy the results of his investigations upon the color of water. He proved that perfectly pure water in a tube 10 meters long had adistinctly blue color, while it ought, according to Tyndall, to lookred. Spring also showed that water in which carbonate of lime, silica, clay, and salts were suspended in a fine state of division offered aresistance to the passage of light that was not inconsiderable. Sincethe red and violet light of the spectrum are much more feeble than theyellow, the former will be completely absorbed, while the latter passesthrough, producing, with the blue of the water itself, different shadesof green. 

 * * * * *

There is to be held in Paris this year, from the 1st to the 22d of July, an insect exhibition, organized by the Central Society of Agricultureand Insectology. It will include (1) useful insects; (2) their products, raw, and in the first transformations; (3) apparatus and instrumentsused in the preparation of these products; (4) injurious insects andthe various processes for destroying them; (5) everything relating toinsectology. 

 * * * * *

A catalogue, containing brief notices of many important scientificpapers heretofore published in the SUPPLEMENT, may be had gratis at thisoffice. 

 * * * * *

THE SCIENTIFIC AMERICAN SUPPLEMENT. 

PUBLISHED WEEKLY. 

TERMS OF SUBSCRIPTION, $5 A YEAR. 

Sent by mail, postage prepaid, to subscribers in any part of the UnitedStates or Canada. Six dollars a year, sent, prepaid, to any foreigncountry. 

All the back numbers of THE SUPPLEMENT, from the commencement, January1, 1876, can be had. Price, 10 cents each. 

All the back volumes of THE SUPPLEMENT can likewise be supplied. Twovolumes are issued yearly. Price of each volume, $2. 50, stitched inpaper, or $3. 50, bound in stiff covers. 

COMBINED RATES--One copy of SCIENTIFIC AMERICAN and one copy ofSCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, $7. 00. 

A liberal discount to booksellers, news agents, and canvassers. 

MUNN & CO. , PUBLISHERS, 261 BROADWAY, NEW YORK, N. Y. 

 * * * * *

PATENTS. 

In connection with the SCIENTIFIC AMERICAN, Messrs. MUNN & Co. AreSolicitors of American and Foreign Patents, have had 38 years'experience, and now have the largest establishment in the world. Patentsare obtained on the best terms. 

A special notice is made in the SCIENTIFIC AMERICAN of all Inventionspatented through this Agency, with the name and residence of thePatentee. By the immense circulation thus given, public attention isdirected to the merits of the new patent, and sales or introductionoften easily effected. 

Any person who has made a new discovery or invention can ascertain, freeof charge, whether a patent can probably be obtained, by writing to MUNN& Co. 

We also send free our Hand Book about the Patent Laws, Patents, Caveats. Trade Marks, their costs, and how procured, with hints for procuringadvances on inventions. Address

MUNN & CO. , 261 BROADWAY, NEW YORK. 

Branch Office, cor. F and 7th Sts. , Washington, D. C.