AMERICAN SOCIETY OF CIVIL ENGINEERS Instituted 1852 TRANSACTIONS Paper No. 1157 THE NEW YORK TUNNEL EXTENSION OF THE PENNSYLVANIA RAILROAD. THE SITE OF THE TERMINAL STATION. [1] By GEORGE C. CLARKE, M. Am. Soc. C. E. The purpose of this paper is to describe the preliminary work for andthe preparation of that portion of the site for the Terminal Stationin Manhattan, of the New York Tunnel Extension of the PennsylvaniaRailroad, which was constructed under the direction of the ChiefEngineer of the East River Division, including the disposal of materialexcavated from all parts of the Terminal construction and the tunnels onthe East River Division. As outlined in the paper by Brigadier-General Charles W. Raymond, M. Am. Soc. C. E. , Chairman of the Board of Engineers, the track yard of thestation, Plate LIII, extends from the east line of Tenth Avenue eastwardto points in 32d and 33d Streets, respectively, 292 and 502 ft. East ofthe west line of Seventh Avenue. The width of the available area attrack level at Tenth Avenue is 213 ft. , continuing at this width towithin 182 ft. Of the west line of Ninth Avenue, where, by an offsettoward the south, it is increased to 355 ft. This width is held to apoint 5 ft. East of the east line of Ninth Avenue, where, by an offsettoward the north, it is increased to 509 ft. , which width continues tothe west line of Seventh Avenue, where it divides into two fan-shapedareas. The north area has a width of about 170 ft. And the south one, 160 ft. , at the house line, each area tapering gradually to the widthof the standard three-track tunnel at the east ends, noted above in 33dand 32d Streets. Additional track room for four tail-tracks is gained bythe construction of two double-track tunnels under Ninth Avenue at 33dStreet, their center lines being parallel to the street and 45. 5 and84. 5 ft. Distant, respectively, from the north house line. An additionalwidth of 24. 5 ft. Is occupied on the north from 277. 5 ft. To 543. 5 ft. West of the west line of Seventh Avenue, where the buildings on thenorth side of 33d Street have been torn down and the enclosing wall setback in anticipation of a future outlet to 34th Street; and on thesouth, from 459 ft. To 597 ft. West of the west line of Seventh Avenue arectangular offset of 124 ft. Encloses the area occupied by the ServiceBuilding. The total area above outlined is the space occupied at tracklevel, and amounts to 28 acres, of which the portion west of the easthouse line of Ninth Avenue and south of a line 107. 3 ft. South of thesouth line of 33d Street is a part of the North River Division, and wasconstructed under the direction of the engineers of that Division; thefan-shaped areas east of the west house line of Seventh Avenue wereconstructed under the direction of the Chief Engineer of ElectricTraction and Terminal Station Construction. [Illustration: Plate LIII. Pennsylvania Station, New York City: Plan Showing Area at Track Level] In June, 1903, when the writer's connection with the work began, thepreliminary surveys had been completed and the location and extent ofthe Terminal track area had been fixed, in so far as the city blocks tobe occupied were concerned. This contemplated area, however, did notinclude the portion between Ninth and Tenth Avenues, that being addedsubsequently. The elevation of the track level had also been fixed bythe requirement in the agreement with the City that no part of thepermanent structure should approach within 19 ft. Of the surface underany avenue or under any street except within the Terminal area. Thenearest approach of the tracks to the surface is at a point 320 ft. Eastof Eighth Avenue, where the top of the rail is 40 ft. Below the 31stStreet curb line. WASH-BORINGS. The general plan of enclosing the area in retaining walls having beenadopted, wash-borings were taken, for the purpose of determining thebest location for the walls, the depth of rock, and the nature of thematerial overlying it. These borings were made along both curb lines ofSeventh Avenue, the east curb line of Ninth Avenue, the north curb lineof 33d Street, and the south curb line of 31st Street. The borings, as arule, were taken at intervals of approximately 100 ft. , some deviationin these intervals being made in order to prevent injury to water, gas, and sewer connections, and, if the elevation of the surface of the rock, as determined by one of these borings, corresponded fairly well withthe borings on either side of it, no intermediate borings were taken. When a discrepancy appeared, a boring was taken midway between thetwo non-corresponding ones, and if the information obtained from theintermediate boring failed to account for the discrepancy, others weretaken at the quarter points of the original 100-ft. Interval. The dotted lines on Fig. 1 show the profiles of the surface of the rockunderlying 31st and 33d Streets, on the line of the borings, constructedfrom the elevations obtained by them; the solid lines show the profilesof the actual surface of the rock as found when uncovered. It will benoted that, except in three cases, Borings 313, 328, and 333, the twoprofiles correspond very closely at the points where the borings weremade, but they differ widely between those points, a variation of 5 ft. Being common; there is a variation of 14 ft. Between Borings 324 and327, and between Nos. 337 and 340; and of 12 ft. Between Nos. 333 and335, and between Nos. 312 and 313, while an extreme variation of 17 ft. Is shown between Nos. 303 and 305. At each of the points where thevariation is great the interval between borings is the full 100 ft. , andit is quite apparent that, if a definite idea is to be obtained of theelevation of the surface of the rock in Manhattan, borings must be takenat shorter intervals. The necessary width of trench for the construction of the retainingwalls was determined by the elevation of the rock, as shown by theborings, and only in the case of the dip between Borings 303 and 305did the variation lead to any difficulty. The trench at that point hadto be widened after rock was reached. This depression corresponded veryclosely in location to that of one arm of the creek shown on GeneralViele's map of 1865, [2] the bed of that stream, or one in approximatelythe same location, being clearly marked across the excavation bysmoothly-worn rock and well-rounded boulders. The original stream, however, seemed to have turned in a westerly direction under 31st Streetto Eighth Avenue instead of crossing, as shown on General Viele's map. [Illustration: Fig. 1. PROFILE OF ROCK SURFACES IN THIRTY-FIRST AND THIRTY-THIRD STREETS, BETWEEN SEVENTH AND NINTH AVENUES] SEWERS. The arrangement of the sewers in the streets in the vicinity of theTerminal Site, previous to the beginning of the construction, and thedrainage area tributary to those sewers, is shown by Fig. 2. The mainsewer for this district was in Eighth Avenue, and was a 6-ft. Circularbrick conduit within the Terminal area. The sewers leading to it fromthe west, in 31st, 32d, and 33d Streets, were elliptical, 3 by 2 ft. , and egg-shaped, 4 ft. By 2 ft. 8 in. , although in no case did they drainmore than one block, and they were on a heavy grade. Draining intoEighth Avenue from the east, the one on 31st Street was 4 ft. By 2 ft. 8 in. , egg-shaped, and drained a length of two blocks, and those on 32dand 33d Streets were circular, 4 ft. In diameter, and drained theterritory for three blocks, or as far east as Fifth Avenue. There wereno sewers in Seventh Avenue within the Terminal area, except smallvitrified pipes, each less than 200 ft. In length. It was desirable that the size and number of the sewers in the streetsand avenues surrounding the Terminal should be reduced to a minimum, onaccount of the difficulty of caring for them during construction andalso to reduce the probability of sewage leaking into the undergroundportion of the work after its completion. With this in view, the planwas adopted of building an intercepting sewer down Seventh Avenue fromnorth of 33d Street to the 30th Street sewer, which, being a 4-ft. Circular conduit, was sufficiently large to carry all the sewage comingfrom east of Seventh Avenue and south of 34th Street. It was decided tobuild this sewer of cast iron where it crossed the proposed constructionwork, and also to replace with cast iron the brick sewers on 31st, 32d, and 33d Streets from Seventh Avenue to a point east of the west end ofthe standard tunnel section, and also the sewer on Eighth Avenue fromthe north side of 33d Street to the south side of 31st Street. Thisarrangement permitted: first, the removal of the sewer in 32d Streetbetween Seventh and Eighth Avenues, which was necessary, as that streetwas to be excavated; second, the reduction of the sewer in Eighth Avenuefrom a 6-ft. To a 5-ft. Circular conduit; and, third, assuming that thesewage and drainage from the Terminal would be pumped directly to thesewers in the avenues, the reduction of the sewers in 31st and 33dStreets, from Seventh to Ninth Avenue, to 15-in. Vitrified pipes, exceptwest of the Service Building in 31st Street, to accommodate whichsection, a larger sewer was required. The sewer in 32d Street, fromNinth to Eighth Avenue, of course, could be dispensed with in anyarrangement, as all the area tributary to it was to be excavated. [Illustration: Fig. 2. PLAN SHOWING LAYOUT OF SEWER IN CATCHMENT AREA ABOUT TERMINAL STATION] GAS AND WATER MAINS. A rearrangement of the gas pipes in the three streets crossing theTerminal site was necessary. These pipes were of two classes: trunkmains and service mains. Fortunately, there were but two trunk mainsin the three streets, one a 20-in. In 31st Street from east of SeventhAvenue to Ninth Avenue, the other a 16-in. In 32d Street from east ofSeventh Avenue to Eighth Avenue. The 20-in. Main was relaid from SeventhAvenue and 31st Street down Seventh Avenue to 30th Street and throughthat street to Ninth Avenue. The 16-in. Main was relaid from SeventhAvenue and 32d Street north to 34th Street and through that street toEighth Avenue. The service mains in 32d Street were no longer required, and were taken up and not replaced. The houses on 31st and 33d Streetswere provided with service by two 6-in. Wrought-iron mains back of theretaining walls in each street, that location being chosen to avoiddamage by gas drip to the water-proofing of the street bridges. As thepermanent structures under the avenues were not to approach the surfacenearer than 19 ft. , only slight rearrangements, sufficient to permit thenew sewers and water lines to be laid, were necessary. There were no large water mains to be cared for, in fact, those in thestreets were too small for ample fire protection, being only 6 in. Indiameter. The main in 32d Street was taken up and not replaced, andthose on 31st and 33d Streets were replaced by 12-in. Pipes laid backof the retaining walls. No changes were necessary in the mains in theavenues, but, before approving the rearrangement for the streets, theDepartment of Water Supply, Gas and Electricity added a 48-in. Main inEighth Avenue to be laid as a part of this construction, the pipe beingsupplied by the City. LOCATION AND DESIGN OF RETAINING WALLS. The plans, from the earliest stages, contemplated founding theretaining wall on the surface of the rock, where of suitable quality, and afterward excavating the rock in front of the toe of the wallto sub-grade. This plan was definitely adopted soon after the boringswere completed, on account of the great danger of blasting out largequantities of rock in timbered trenches close to buildings founded onsoft material, and also to avoid the additional cost and delay thatwould have been caused by carrying the walls to sub-grade. The retainingwalls in Seventh Avenue, south of the viaduct, and in Ninth Avenue, north of the viaduct, were not governed by the same conditions as in thestreets. The dip and quality of the rock at both points required thatthe walls be carried to sub-grade, and they are, in fact, face walls;the Ninth Avenue wall, in particular, having little thrust to sustain, is very light. The results aimed at in the design and location of the retaining wallsin 31st and 33d Streets were: _First. _--A perfectly stable wall under all conditions that might reasonably be expected; _Second. _--As much room as possible at the elevation of the top of rail; _Third. _--The least necessary interference with adjoining property during construction; and, _Fourth. _--The most economical wall that would fulfill the other conditions. As stated in the paper by Alfred Noble, Past-President, Am. Soc. C. E. , the third stipulation required the relinquishing of a portion of thespace under these streets granted by the City, but it was finallydecided not to approach the south house line of 31st Street with theback of the walls nearer than 9 ft. , while on 33d Street the extremeposition of the back was fixed at the north line, as there were nobuildings, except those belonging to the Railroad Company, on the houseline at the low points in the rock. The assumptions made in designing the wall were as follows: _First. _--Weight of concrete, 140 lb. Per cu. Ft. _Second. _--Weight of material from the surface of the ground to a depth of 12 ft. (which was shown by tests made in bore-holes to be the elevation of the ground-water surface), 100 lb. Per cu. Ft. ; and angle of repose, 30 degrees. The distance of 12 ft. Below the surface was the depth of the inverts of the sewers, which undoubtedly drained the ground above them, thus accounting for the standing of the ground-water in planes practically parallel with the surface. _Third. _--Weight of buildings back of wall neglected, as that of the present type will about equal the cellars filled with material at 100 lb. Per cu. Ft. , and if large buildings are erected in the future they will undoubtedly be carried to rock. _Fourth. _--Reaction from superstructure, live and dead load, 20, 000 lb. Per lin. Ft. Of wall. _Fifth. _--Weight of materials below the 12-ft. Line, 124 lb. Per cu. Ft. , ascertained as follows: The material was considered as weighing 165 lb. Per cu. Ft. In the solid, and having 40% of voids filled with water at 62. 5 lb. Per cu. Ft. , the resulting weight being (165 × 60/100) + (62. 5 × 40/100) = 124 lb. Per cu. Ft. Various angles of repose were used for this material in theinvestigation, and it was finally decided that 30° was the greatestangle that could be expected, whereas the worst condition that could beanticipated was that the sand and water would act separately and give apressure as follows: Hydraulic pressure from liquid weighing 62. 5 lb. Per cu. Ft. Pluspressure from sand with angle of repose at 30° and weight as follows: Weight of 1 cu. Ft. In air = 165 × 60/100 = 99 lb. Weight of water displaced by 1 cu. Ft. = 60/100 × 62. 5 lb. = 37. 5 lb. Weight in water, therefore = 61. 5 lb. Per cu. Ft. These combined weights, of course, are equal to the weight of thecombined material in the previous assumption. _Sixth. _--The usual requirement that the resultant of both horizontal and vertical forces should, at all points, fall within the middle third of the wall, or, in other words, that there should be no tension in the concrete. [Illustration: Plate LIV. Diagram Showing Widths of Base of Retaining Wall Required for Different Batters and Pressures, Pennsylvania Station] With these assumptions, investigation was made of walls with variousbatters and differently designed backs. This investigation developed thefact that the reaction from the superstructure was so great that, foreconomy, both in first cost and space occupied, the batter must besufficient to cause that reaction to fall within or very close to themiddle third. Nothing could have been gained by having that reactionfall back of the front of the middle third, as the wall was requiredto be stable against the full pressure before the superstructure waserected, and in case it should ever be removed; or, to state the mattermore clearly, the reaction from the superstructure was so great incomparison to the weight of the wall, that, if it fell in front of theresultant of all the other forces, the width of base required would begreatly increased to make the wall stable after the superstructure waserected; whereas, if the reaction from the superstructure fell back ofthe resultant of all the other forces, the width of base could not becorrespondingly decreased without danger of the wall being overturnedbefore the superstructure was erected. The least batter that wouldanswer those conditions was found to be 2 in. Per ft. For convenience in designing, and economy in constructing, thesteelwork, the faces of the bridge seat and of the backwall were laidparallel to the center line of the Terminal, and in elevation on lineparallel to the top of the curb and as near to it as the economicaldepth of steel would permit, without bringing the finished constructionabove the plane fixed in the ordinance. As there is a variation of 13ft. In the elevation of the top of the curb of 31st Street above the topof rail and a variation of 18 ft. In 33d Street, a uniform batter, withthe top parallel to the center line, would produce a toe varying indistance from it and from the other constructions. It was decided, therefore, for the sake of appearance, to make the face of the wall(or wall produced) at the top of rail parallel to the center line, and to vary the batter accordingly, using the 2-in. Batter previouslymentioned as the minimum. This gave a maximum batter of 3 in. Per ft. Thevariation is so gradual that it is unnoticeable, and is not sufficientto introduce any complications in construction. The wall was designed with a stepped back, primarily to allow thewater-proofing and brick protection to be held in position more readily. The first step was put at 13 ft. Below the surface of the ground. Thisgave a vertical back above that point for a 3-in. Battered face, and aslightly battered back for sections having a less batter in front. Belowthat point a step was added for each 5 ft. Of depth to the elevationof the top of rail, or to the foundation of the wall if above thatelevation. As the horizontal distance of the heel of the wall, at itsgreatest width, from its face at the top of rail would determine theeffective room to be occupied by the wall, it was determined to make theback vertical below the top of rail and gain the necessary increase inwidth below that point by making a heavy batter on the face. The type of wall having been thus determined, calculations were madeof the width of base required for each ¼-in. Batter from 2 to 3 in. , inclusive, first for a depth of 13 ft. Below the top of the curb andthen for each 5 ft. Below that elevation, to a depth corresponding tothe distance between the top of the curb and the top of the rail at thepoint of greatest variation. These widths of wall were determined forthe two pressures previously decided on, and curves were then plottedshowing the thickness of wall required for each batter calculated andfor each pressure. They are shown on Plate LIV. The curves in brokenlines represent the widths required for saturated material, and thecurves in dotted lines for hydraulic pressure. Mean curves were thendrawn between each broken and its corresponding dotted curve. These areshown in solid lines, and represent the widths of wall which were usedin the construction. Typical sections of the wall and pipes back of itare shown on Fig. 3. The extreme positions of the back of the wall on the two streets havingbeen determined, as previously stated, the width of base required atthose points fixed the toe of the wall at the top of rail as 254. 5 ft. South of the center line of the Terminal in 31st Street, and 258. 5 ft. North of the center line in 33d Street. [Illustration: Fig. 3. TYPICAL SECTIONS OF RETAINING WALL IN THIRTY-FIRST STREET] CONTRACTS. The construction was done under the following contracts: _1. _--The principal contract, dated June 21st, 1904, was with the NewYork Contracting and Trucking Company, later assigned by that companyto the New York Contracting Company-Pennsylvania Terminal, for theperformance of the following works: (_a_). --The excavation for and construction of a retaining wall in Seventh Avenue, 31st Street, Ninth Avenue, and 33d Street. (_b_). --Excavation over the area enclosed by the retaining wall. (_c_). --The building of sewers and the laying of water and gas pipes. (_d_). --The building of a timber trestle to support the surface of Eighth Avenue between the south side of 31st Street and the north side of 33d Street, and also the surface of 31st and 33d Streets between Seventh and Ninth Avenues. This refers to the trestles left in place on the completion of the work. (_e_). --The building of a trestle and bridging from a point near the west side of Tenth Avenue on the south side of 32d Street, westward to the outer end of Pier No. 62, at the foot of 32d Street. _2. _--The second contract, dated February 10th, 1905, was with the NewYork Contracting Company-Pennsylvania Terminal, for the excavation forand construction of retaining walls for the Manhattan Terminal PowerStation, and the excavation of the area thus enclosed. _3. _--The third contract, dated October 2d, 1907, was with the New YorkContracting Company-Pennsylvania Terminal, for the construction of twotwin tunnels under Ninth Avenue, and other work incidental thereto. Sewers and gas mains laid outside the area covered by the foregoingcontracts were constructed under the following agreements: An agreement, dated August 9th, 1904, between the New York ContractingCompany-Pennsylvania Terminal, and the New Amsterdam Gas Company, for a20-in. Gas main from Seventh Avenue and 31st Street to 30th Street, andthence to Ninth Avenue, the New Amsterdam Gas Company being remuneratedfor the cost by the Tunnel Company. A contract, dated August 24th, 1904, with the New York ContractingCompany-Pennsylvania Terminal, for the construction of sewers in SeventhAvenue and in 32d and 33d Streets east of Seventh Avenue. A contract, dated November 24th, 1908, with the New York ContractingCompany-Pennsylvania Terminal, for the construction of a 16-in. Gas mainfrom Seventh Avenue and 32d Street to 34th Street, and thence to EighthAvenue. All these contracts required that the excavated material be delivered onboard scows to be furnished by the company at the pier at the foot of32d Street, North River. These scows were furnished and the materialwas disposed of from that point by Henry Steers, Incorporated, under acontract, dated August 9th, 1904, which called for the transportation toand placing of all material so delivered in the Pennsylvania RailroadCompany's freight terminal at Greenville, N. Y. The disposal of the excavated material was one of the principal featuresof the work, and, under the above contract, material from those portionsof the Terminal site east of Seventh Avenue and west of Ninth Avenue, and from all substructures work, was disposed of, as well as from theconstructions herein described. The problem differed from that presentedby the usual foundation excavations in New York City in magnitude only, and the methods were not unusual, but were adaptations of the usual onesto exceptionally large work. PIERS AND TRESTLE FOR DISPOSAL. The most rapid and economical handling of all excavated material toscows was made possible by the Tunnel Company procuring from the NewYork Central and Hudson River Railroad Company the pier at the foot of32d Street, North River, known in the earlier stages of the work as PierNo. 62, but subsequently changed to Pier No. 72, and thus referred to inthis paper. This pier was occupied by a freight-shed used by the NewYork Central Railroad Company, under a long-term lease from the City, and that Company had to make numerous changes in their tracks andadjoining piers before No. 72 could be turned over; the contract forthe excavation, therefore, required the contractor to procure any piersneeded previous to and in addition to it. Under this clause of theagreement, the contractor procured one-half of the pier at 35th Street, North River, which was used for the disposal of all material excavatedprevious to May 22d, 1905, on which date Pier No. 72 was first put inservice. As the type of plant the contractor would elect to use could not bedetermined, previous to the letting of the contract, a general plan forPier No. 72 and the trestle approach, suitable for either trains orwagons, was attached to the contract, and the details were worked outafterward. The method adopted was by train, and a two-track approach tothe pier was provided. Beginning on the east side of Ninth Avenue, atthe south line of 32d Street, at an elevation of 20 ft. Below thesurface, crossing under Ninth Avenue and to the center line of 32dStreet, it rose on a 1. 5% grade in open cut to the surface of 32d Streetat a point 500 ft. West of Tenth Avenue, from which point it rose abovethe surface of the street on a timber trestle to Tenth Avenue, which wascrossed overhead. West of Tenth Avenue the line changed by a reversecurve to the south sidewalk of 32d Street, and continued on a timbertrestle, practically level, to the New York Central Yard tracks nearEleventh Avenue. These tracks and Eleventh Avenue were crossed overheadon a through-truss, steel bridge, and a column-and-girder constructionon which the two tracks separated to a distance of 29 ft, between centerlines, so as to bring them directly over the posts of special timberbents which spanned the two house tracks of the New York Centralsouth-bound freight shed, which the trestle here paralleled. Thisposition was held to a point 25 ft. West of the east house line ofTwelfth Avenue, where, by a system of cross-overs and turn-outs, accesswas had from either track to six tracks on the pier. Four of these wereon upper decks, two on the north and two on the south edge of the pier, at an elevation of 41 ft. Above mean high tide, to carry earth and smallrock to chutes from which it was dumped into barges. The other twotracks proceeded by a 5. 3% grade down the center of the pier to thelower deck where, at a distance of 540 ft. From the bulkhead, and beyondthe upper deck construction, they diverged into six, two on the northand two on the south edge of the pier for standing tracks to servederricks, and two down the center for shifting purposes. A siding to thenorth of the two running tracks just west of the bottom of the inclineserved a bank of eight electric telphers. The arrangement of the pier isshown by Fig. 4. The trestle east of the steel structure at Eleventh Avenue had simplefour-post bents, as shown by Bent "_A_, " on Fig. 5, all posts beingvertical, to save room at the street level; the outside posts and thecaps and sills were of 12 by 12-in. Timber; the intermediate posts wereof 8 by 12-in. Timber; and single or double decks of 3 by 8-in. Bracingwere used, depending on the height of the bents. These bents were framedon the ground in position and raised by hand. West of Tenth Avenue, thesills of the bents rested on four 12 by 12-in. Longitudinal timbers, each spanning two bays and breaking joints, for convenience insupporting the trestle while the tunnels were constructed in open cutbeneath. These bents were placed 12 ft. On centers, with one 8 by 16-in. Stringer under each rail, and one 6 by 16-in. Jack-stringer supportingthe overhang of the floor on either side. The bents along the New York Central freight shed had but two posts of12 by 14-in. Yellow pine varying from 26 ft, to 31 ft. 9 in. From centerto center; they had double caps of 12 by 14-in. Yellow pine on edge, nobottom sills or bracing, and the vibration and wind pressure were takencare of by the top bracing and anchorage, as shown by Bent "_G_, " onFig. 6. [Illustration: Fig. 4. PLANT FOR DISPOSAL OF EXCAVATED MATERIALS PIER NO. 72 N. R. ] The method of erection was as follows: An excavation was made on theline of each post, 4 ft. Deep and from 4 to 5 ft. Square, depending onwhether it was for a single or reinforced post; 6 in. Of concrete wasplaced in the bottom, and on this were laid, at right angles to thecenter of the trench, three 8 by 12-in. Timbers varying in length withthe excavation from 3 to 4 ft. To these timbers was drifted one 12 by12-in. Timber of the same length as those in the bottom row, but atright angles to them. Elevations were then taken on top of the 12 by12-in. Timber, and the bent was framed complete and of correct height. The framing was done south of the line of the trestle and west of thefreight-house. The framed bents were picked up by a small two-boomtraveler carrying two double-drum, electric, hoisting engines, and runforward into position. A hole had previously been made in the metalgutter and canopy of the freight-house, by an experienced roofer, andin the freight platform underneath, and, as soon as the bent had beendropped into position, it was firmly drifted to the foot-blocks, previously described, and the excavation made for them was filled withconcrete well rammed about the blocks and rounded off 6 in. Above thesurface of the ground. Secure flashings, in two sections, were then madeabout the posts to cover the holes made in the gutter and roof, thebottom sections being firmly soldered to the roof or gutter, and the topsections, which lapped over the bottom and cleared them 2 in. In alldirections, were firmly nailed to the posts and the joints leaded. Thisarrangement allowed the bents to move slightly, and at the same timemade the roof and gutter water-tight. These bents were placed 16 ft. Oncenters to correspond with the spacing of the doors of the freight shed. Under the cross-overs near Eleventh Avenue, where the tracks had tobe supported in different positions on the caps, and could no longerbe kept over the posts, the caps were trussed and the posts werereinforced, as shown on Bents "_J_, " "_H_, " and "_K_, " Fig. 5. [Illustration: Fig. 5. DETAIL OF BENTS FOR MATERIAL TRESTLE] The trusses for the through bridge over the tracks were erected onSunday, April 16th. The two trusses, one 122 ft. And the other 165 ft. 8in. From center to center of end posts, had been assembled and riveted, lying flat on cribwork a few feet above the ground, south of thepermanent position and between the New York Central tracks and EleventhAvenue. On the date stated, the contractor, having been given permissionto block the Central's tracks from 5 a. M. To 9 p. M. , erected a largesteel gin pole just south of the correct position of the center of thenorth truss, which was then dragged, from the place where it had beenassembled, across the railroad tracks until the center of the bottomchord was vertically under its true position, the truss still lying flatand about at right angles to the center line of the bridge. Chains weremade fast to the top chord at the middle panel of the truss, which wasthen turned up to a vertical plane, raised to its permanent position, and guyed. The gin pole was then shifted and the operation repeated withthe longer truss, after which, half of the floor beams and a part of thetop laterals were bolted in position and the guys were removed, thebridge being thus erected without the use of falsework of any kind. During the lifting there was no sag in either truss that could benoticed by the eye. Fig. 1, Plate LV, shows the bridge erected, withthe exception of the tight timber fence. Pier No. 72 is directly over the North River Tunnels. When it was turnedover by the New York Central Railroad Company, the contractor for theconstruction of those tunnels tore down the shed and removed the deckand such piles as were in the path of the tubes. This left standing thefour northernmost, the four southernmost and two centers rows of pilesfor the entire length of the pier. An additional row of piles was thendriven on either side of the two center rows, and battered so that atthe elevation of the tunnels they would be close to the center rowsand leave as much clear space as possible. The pier, therefore, wasconstructed of three independent lines of four-post bents, which, however, rested on sills which were continuous throughout the width ofthe pier, as shown by Figs. 2 and 3, Plate LV. [Illustration: Fig. 6. DETAIL OF BENTS FOR MATERIAL TRESTLE. ] The bents for the upper floors of the pier were double-decked, with12 by 12-in. Posts, sills, intermediate and top caps, and 3 by 8-in. Longitudinal and cross-bracing. The bents for the incline were similar, except that those below 16 ft. In height were of single-deckconstruction. The spacing of the bents varied from 9 ft. 6 in. To 12ft. , except the three outer bays, which had a span of 23 ft. , all toagree with the position of the pile bents. The double-deck constructionextended for the full length of the original pier. A single-deckextension, of full width and 180 ft. In length, was subsequently builtfor the accommodation of four derricks for handling building materialand large rock. The piles for this extension were driven in three setsof four rows each, similar to those in the old portion of the pier, except that the bents were driven with a uniform spacing of 15 ft. Between centers. The three sets of bents were topped separately with12 by 12-in. Caps and 12 by 12-in. Dock stringers; they were braced withboth cross and longitudinal low-water bracing, and were tied together bya continuous 12 by 12-in. Timber over the dock stringers and 12 by12-in. Packing pieces from stringer to stringer, each of these tiesbeing supported in the center of the span over the tunnels by two 2-in. Hog rods, Section "_A-A_, " Fig. 4. The south side of the upper deck of the pier carried three sets of ninehoppers, each set covering 90 ft. , a little less than the full lengthbetween bulkheads of the largest deck scows, with 70 ft. Clear betweensets, to allow for the length of a scow outside of the bulkhead and topermit the free movement of boats. Each hopper occupied the full spacebetween two bents, and, as the caps were topped by strips of timber oftriangular section, with a width of 12 in. On the base and a height of6 in. , protected by a 6 by 6-in. Steel angle, each set of hopperspresented 90 lin. Ft. Of continuous dumping room. The bottoms of thehoppers, set at an angle of 45°, were formed by 12 by 12-in. Timberslaid longitudinally, running continuously throughout each set, andcovered by 3-in. Planking. The partitions were formed with 4-in. Plankssecurely spiked to uprights from the floor of the hoppers to the caps;these partitions narrowed toward the front and bottom so as to fitinside the chutes. Each hopper was lined on the bottom and sides with½-in. Steel plates, and the bottoms were subsequently armored with 2 by1-in. Square bars laid 3 in. On centers and bolted through the 12 by12-in. Flooring of the hoppers. The chutes, extending from the bottom ofthe hoppers, were 20 ft. Long and 7 ft. Wide, in the clear; they wereformed entirely of steel plates, channels, and angles, and weresupported from the upper deck of the pier by chains; their lower endswere 17 ft. Above mean high tide and 14 ft. 6 in. From the string pieceof the pier. The hoppers and chutes are shown by Fig. 1, Plate LVI. [Illustration: Plate LV. Material Trestle Over N. Y. C. & H. R. R. R. Co. 's Tracks; and Construction of Pier No. 72, North River Fig. 1. --Material Trestle Over N. Y. C. & H. R. R. R. Co. 's Tracks. Fig. 2. --Material Trestle Under Construction on Pier No. 72, North River, Showing Clear Water Over Tunnel Location. Fig. 3. --Pier No. 72, North River, Showing Incline as Reconstructed For Locomotives. ] A length of 150 ft. Of the north side of the pier was for the use of thecontractor for the North River tunnels; it was equipped with a set ofnine chutes similar to those for the south side; they were used butlittle, and were finally removed to make room for a cableway forunloading sand and crushed stone. At the foot of the incline there was a bank of eight telphers runningon rails securely bolted to the tops of 20-in. I-beams, which were hungfrom stringers resting on the upper caps. The beams were erected inpairs, each pair being securely braced together and to the trestle poststo prevent swaying. Each telpher occupied the space between two bents, about 10 ft. , so that the entire bank commanded a length of 80 ft. , which was approximately the length of a rock scow between bulkheads. Allsupports for the telphers were provided as a part of the trestle, butthe machines themselves were a part of the contractor's plant. Four derricks were erected on the extension, two on the north and two onthe south edge of the pier, supported on bents at a sufficient elevationabove the floor to clear a locomotive. After most of the earth had been excavated, the out-bound set of hopperson the south side of the pier was removed, and two derricks were erectedin their place and used for unloading sand, crushed stone, and otherbuilding material. PLANT. As the use of the 35th Street pier for the disposal of material requiredthat the mode of transportation should be by dump-wagons drawn byhorses, the plant in use by the contractor during that periodnecessarily differed in many respects from what it was later, when PierNo. 72 was available. Therefore, the nature of the plant during eachperiod will be stated. The plant for each period will be divided intofive classes: 1. --Central Plant: (_a_) Power-Generating Plant. (_b_) Repair Shops. 2. --Retaining-Wall Plant. 3. --Pit-Excavating Plant. 4. --Transportation Plant. 5. --Dock Plant. Horse-and-Truck Period: July 11th, 1904, to May 22d, 1905. _1. _--_Central Plant. _ (_a_). --_Power-Generating Plant. _--The contractor's first centralgenerating plant was established in a 35 by 85-ft. Steel-framed buildingcovered with corrugated iron, the long side being parallel to NinthAvenue and 15 ft. From the east house line, and the north end 43 ft. South of the south house line of 32d Street. The foundations for thebuilding and machinery were of concrete, resting on bed-rock, the floorbeing 20 ft. Below the level of the Ninth Avenue curb. The south end ofthe building was the boiler-room and the north end the compressor-room, the two being separated by a partition. Coal was delivered into a largebin, between the boiler-house and Ninth Avenue, its top being level withthe street surface, and its base level with the boiler-room floor. At the end of the horse-and-truck period the plant consisted of: Two Rand, straight-line compressors, 24 by 30 in. , having a capacity of 1, 400 cu. Ft. Of free air per min. When operating at 86 rev. Per min. And compressing to 80 lb. Above atmospheric pressure. One 10 by 6 by 10-in. , Worthington, steam, plunger pump. Three horizontal boilers of the locomotive type, each of 125 h. P. (_b_). --_Repair Shops. _--The repair shops, which included blacksmith, machine and carpenter shops, were located on the first floor of a 40 by70-ft. Two-story frame structure, which was in the pit on the north sideof 31st Street, 48 ft. East of Ninth Avenue. The second floor was on thestreet level, and was used as a storehouse for hand-tools and smallplant. The blacksmith shop contained: Four forges with hand blowers, fouranvils, and hand-tools. The machine shop contained: One drill press, one shaper (14-in. Stroke), one 18-in. Swing lathe, and one 6-in. Bed lathe. The carpenter shop contained: One circular saw, one wood lathe, andhand-tools. The plant in both machine and carpenter shops was operated by one7½-h. P. General Electric motor, the current for which was obtained fromthe Edison Electric Heat, Light, and Power Company. [Illustration: Plate LVI. Material Trestle Showing First Chutes in Operation; and Views of East and West Pits at Terminal Site Fig. 1. --Material Trestle, Showing First Chutes in Operation. Fig. 2. --East Pit, Steam Shovel Loading Excavated Material on Car. Fig. 3. --West Pit, Showing Condition on June 28th, 1905. ] _2. _--_Retaining-Wall Plant. _ Three cableways, with 35-ft. Towers of 12 by 12-in. Yellow pine timber capable of spanning 350 ft. , and operated by 7 by 10-in. Double-drum Lambert hoisting engines mounted with 25-h. P. Lambert upright boilers. Five stiff-leg derricks, with masts from 35 to 50 ft. Long and booms from 45 to 60 ft. Long, operated by 7 by 10-in. Lambert double-drum and swinging gear engines, mounted with 25-h. P. Upright Lambert boilers. Six Cameron pumps, varying in size from 7 by 6 by 13 in. To 10 by 8 by 16 in. The first dimension referring to the diameter of the steam cylinder, the second to that of the water, and the third to the stroke. Five Rand sheeting drivers. Two Ransome ¾-cu. Yd. Concrete mixers, mounted on frame, with kerosene driving engine. Drills drawn from pit plant as required. _3. _--Pit-Excavating Plant. One guy derrick, 50-ft. Mast and 45-ft. Boom, operated by a Lambert two-drum and swing-gear hoisting engine, with Lambert 25-h. P. Upright boiler. Three stiff-leg derricks, similar to those used on the retaining wall work. Three Bucyrus, 70-ton steam shovels with 3½-cu. Yd. Dippers. One traveling derrick, built with an A-frame of 12 by 12-in. Timbers, 15-ft. Mast, and 25-ft. Boom; the traveler carried an engine and boiler similar to those used on the stiff-leg derricks, and was used on the Seventh and Eighth Avenue sewers, as well as in the pit. Ten Rand-Ingersoll rock drills, Nos. 1, 3¼, and 4. One Reliance stone crusher (nominal capacity 17 tons of crushed stone per hour) belt-driven by 50-h. P. Engine. _4. _--_Transportation Plant. _ During the whole of the first period the transportation plant consisted of two-horse trucks and snatch teams as needed. The number varied greatly from 25 at the beginning and end of the period to an average of 135 from August 1st to December 1st, 1904, about 10% of the total number of teams being used as snatch teams. _5. _--_Dock Plant. _ The only machinery used on the dock during the horse-and-truck period was one stiff-leg derrick similar in size and operation to those described under the head of retaining-wall plant. The plant described above does not represent that which was used duringthe whole of the horse-and-truck period, but what had accumulated at theend of it. The power-generating plant might almost have been omittedfrom this period, as the first compressor did not begin running untilFebruary, 1905. Previous to that time, the power for drilling, pumping, driving, sheeting, etc. , was steam furnished by the boilers whichsubsequently drove the compressors, these being brought on the groundand fired as occasion required. Train-Disposal Period, Beginning May 22d, 1905. At the beginning of this period there had been excavated 242, 800 cu. Yd. Of earth and 22, 800 cu. Yd. Of rock, of the total excavation of 803, 500cu. Yd. Of earth and 804, 000 cu. Yd. Of rock included in the principalcontract, leaving to be excavated under that contract 560, 000 cu. Yd. Ofearth and 781, 200 cu. Yd. Of rock, and an additional contract had beenlet to the New York Contracting Company for the terminal power station, which increased the earth by 16, 500 and the rock by 15, 500 cu. Yd. During the year following, contracts for the east and west portions andthe sub-structures were let, which brought the total to be excavated, after the beginning of the train-disposal period, up to 681, 000 cu. Yd. Of earth and 1, 494, 000 cu. Yd. Of rock. The central plant, transportation plant, and dock plant were usedindiscriminately on all these contracts, and, as no separation can bemade which will hold good for any appreciable length of time, the plantin those classes will be stated in total. The retaining-wall and pitplant here given include that used on the principal contract andterminal power station only. The power-generating plant given underthe horse-and-truck period was doubled at the beginning of thetrain-disposal period, but it was still insufficient for the work thenunder contract, and the additional contracts necessitated a greaterincrease. The location had also to be changed to permit the excavationof the rock under Ninth Avenue. The old stone church fronting on 34thStreet, between Seventh and Eighth Avenues, a building 68 ft. Wide and92 ft. Long, made a roomy and very acceptable compressor-house. Thewooden floors and galleries were removed, and good concrete foundationswere put in, on which to set the plant; the walls, which were cracked inseveral places, were trussed apart and prevented from moving outward bycables passed about the pilasters between the windows. The boilers were erected south of the church, an ash-pit being firstbuilt, the full width of it, with the floor on a level with thebasement. The rear wall of the church formed the north wall of theash-pit, and the south wall and the ends were built of concrete. Theboilers were set with the fire-doors toward the rear wall of thebuilding, and 7 ft. Distant from it, and above this fire-room and theboilers there was erected a coal-bin of 500 tons capacity. The rear wallof the compressor-house formed the north wall of the bin, the sectionof which was an isosceles right-angled triangle. Coal was delivered bydumping wagons into a large vault constructed under the sidewalk on 34thStreet, and was taken from there to the bin by a belt conveyor. The plant for the second period was as follows: _1. _--_Central Plant. _ (_a_). --_Power-Generating Plant. _--The plant in the engine-roomconsisted of: Three Rand straight-line compressors from the original power plant at Ninth Avenue and 32d Street. One Ingersoll straight-line compressor from the old power-house. One Rand duplex Corliss, 40 by 48-in. Air-compressor, with both air and steam cylinders cross-compounded, and a capacity of 5, 600 cu. Ft. Of free air per min. Compressed to 80 lb. At 70 rev. Per min. Three Rand duplex, 30 by 30-in. , compressors, connected with 525-h. P. , 6, 600-volt, General Electric motors, with a capacity of 3, 000 cu. Ft. Of free air per min. Compressed to 80 lb. At 125 rev. Per min. Two 10 by 6 by 10-in. Worthington steam plunger pumps. One 7½-h. P. General Electric motor for driving the Robbins belt coal conveyor. One forced-draft fan (built by the Buffalo Forge and Blower Company), driven by an 8 by 10-in. Buffalo engine. In the boiler-room there were three 500-h. P. Sterling water-tubeboilers. (_b_). --Repair Shops. --The repair shops remained in their old locationuntil sufficient room had been excavated to sub-grade in the lot eastof Eighth Avenue, and then they were moved to the old Ninth Avenuepower-house which had been erected at that point. The contents of theblacksmith shop remained the same as for the first period. The equipmentof the machine shop was increased by one 18-ton trip-hammer operated byair and one bolt-cutting machine, size 1 in. To 1½ in. The carpentershop remained the same except that the electric motor was replaced by a25-h. P. Single-cylinder air motor; there was added to the repair shop adrill shop containing: Four forges with compressed air blowers, fouranvils, two Ajax 20-ft. Drill sharpeners, and one oil blower forge. _2. _--_Retaining-Wall Plant. _ The retaining-wall plant was identical with that described for the firstperiod, with the addition of two Ransome 1-cu. Yd. , concrete mixers, with vertical engines mounted on the same frame, using compressed air. _3. _--_Pit-Excavating Plant. _ The pit-excavating plant included that listed for the first period and, in addition, the following: One Vulcan, 30-ton, steam shovel, with 1-cu. Yd. Dipper and a vertical boiler. One Ohio, 30-ton, steam shovel, with 1-cu. Yd. Dipper and a vertical boiler. Four guy derricks (50 to 80-ft. Masts and 45 to 60-ft. Booms), operated by Lambert 7 by 10-in. Engines, with two drums and swinging gear, mounted with 25-h. P. Vertical boilers, but driven by compressed air. Seventy Ingersoll-Rand rock drills, Nos. 1, 3¼, and 4. Two Rand quarry bars, cutting 10 ft. In length at one set-up, and mounted with No. 4 drill using a Z-bit. _4. _--_Transportation Plant. _ Twenty-one H. K. Porter locomotives, 10 by 16-in. , and 36-in. Gauge. Three Davenport locomotives, 9 by 16-in. , and 36-in. Gauge. One hundred and forty Western dump-cars, each of 4 cu. Yd. Capacity. One hundred and sixty-five flat cars, with iron skips, each of 4 cu. Yd. Capacity. _5. _--_Dock Plant. _ Four stiff-leg derricks on extension, having 35-ft. Masts and 40-ft. Booms, and each operated by a 60-h. P. Lambert, three-drum, electric, hoisting engine. One stiff-leg derrick, on the south side of the pier on the upper deck, with a 28-ft. Mast operated by a three-drum Lambert engine and a 25-h. P. Vertical boiler. One stiff-leg derrick, on the north side of the dock on the upper deck, used exclusively for bringing in brick, electric conduit, pipe, and other building material, operated when first erected by a three-drum, steam-driven, Lambert, hoisting engine. This engine was later changed to the derrick on the south side of the dock, and a motor-driven Lambert engine from that derrick was substituted. Eight electric telphers. Ninth Avenue Twin-Tunnels Plant. One stiff-leg derrick, previously used in retaining-wall work. One Smith concrete mixer, 1 cu. Yd. Capacity, driven by attached air engine. Two cableways taken from the retaining-wall plant and used for mucking out the tunnels after the center pier had been built; driven by air supplied to the original engine. One Robbins belt conveyor, driven by a 30-h. P. Engine run by air. Three 1-cu. Yd. Hopple dump-cars. CONSTRUCTION. Ground was broken for work under the principal contract on July 9th, 1904, on which date the contractor began cutting asphalt for Trench No. 1 in 31st Street, and also began making a roadway from Ninth Avenue intothe pit just south of 32d Street. _Excavation for Retaining Walls. _--Two essentially different methodswere used in excavating for and building the retaining walls; one, construction in trench, the other, construction on bench. In general, the trench method was used wherever the rock on which the wall was to befounded was 12 ft. Or more below the surface of the street; or, what isperhaps a more exact statement, as it includes the determining factor, where the buildings adjoining the wall location were not founded onrock. In the trench method the base of the wall was staked out on the surfaceof the ground, the required width being determined by the elevation ofthe rock, as shown by the borings. The contractor then added as muchwidth as he desired for sheeting and working space, and excavated to adepth of about 5 ft. Before setting any timber. In some cases the depthof 5 ft. Was excavated before the cableway or derrick for the excavationwas erected, the wagons being driven directly into the excavation andloaded by hand, but, usually, the cableway was first erected, andbuckets were used from the start. After the first 5 ft. Had beenexcavated, two sets of rangers and struts were set, the first in thebottom of the excavation and the second at the level of the streetsurface, supported by posts resting on the bottom rangers. The sheetingwas then set, and all voids back of it were filled with clean earth andwell tamped. The toe of the sheeting was kept level with the bottom ofthe excavation until the ground-water was reached, after which it waskept from 3 to 5 ft. Ahead of the digging. The sheeting used was 3-in. , in variable widths; it was always tonguedand grooved on the side of the trench next to the buildings and in thedeeper excavations on both sides of the trench, and was driven by woodenmauls above the ground-water level, but steam sheeting-drivers were usedbelow that elevation. Struts, rangers, and posts were generally 12 by12-in. Some exceedingly bad material was encountered in the deeper excavations, beds of quicksand being passed through, varying in thickness from 1 to18 ft. , the latter, in 31st Street between Seventh and Eighth Avenues, in the deepest excavation made. After encountering the fine sand in thattrench, no headway was made until a tight wooden cylinder was sunkthrough the sand by excavating the material inside of it and heavilyweighting the shell with pig iron. When this cylinder had reached thegravel, which lay below the sand, it was used as a sump, and the waterlevel was kept below the bottom of the excavation, which permitted goodprogress. Sand continued to flow under the sheeting to such an extent, however, that the front walls of four adjoining buildings were badlycracked and had to be taken down and rebuilt. All the stoops along thistrench settled, and had to be repaired. The bench method of excavating for the retaining wall was very simple, and was used only where the rock lay near the surface and the adjoiningbuildings were founded on it, the overlying material being in such casedry, and consequently firm, little or no shoring was required. Themethod was to extend the pit excavation to a width of 2 or 3 ft. Beyondthe proposed back of the retaining wall, and to carry that width down tothe depth required for its base, below which the excavation was narrowedto 1 ft. Inside of the face of the wall and continued either before itwas built or subsequently. _Retaining-Wall Construction. _--The concrete walls were built insections 50 ft. In length, except where that spacing would bring anexpansion joint under a girder pocket or just on line with a tier ofstruts, in which cases the section was shortened as required. Trencheswere never allowed to remain open at the full depth, the concretingbeing started as soon after the necessary length of rock had beenuncovered as the forms and preliminary work for a section could beprepared. Each section was a monolith, except in a few cases wherevery heavy rains made it impossible to hold the laborers. The various operations in building the concrete wall are shown onFig. 7. Guide-planks, "_a a_, " Section "_A-A_, " were securely spikedto alternate tiers of struts for the length of the section, the faceof each guide-plank being set on line with the intended face of theconcrete wall, and 2-in. Tongued-and-grooved spruce plank were laidalong the guide-plank to the height of the bottom strut and securelybraced from the front sheeting. A 4-in. Brick wall was builtsimultaneously on line with the back of the wall to the height ofthe first step. Where the bottom strut was below that elevation, thebrickwork was left low at that immediate point and built up when thestrut was removed. The brick wall was then water-proofed on the sidetoward the concrete, and loose laps of the water-proofing were allowedto hang over the brickwork and at least 8 in. Down the back. A 6-in. Vitrified pipe drain was then laid along the surface of the rock justoutside of the brick wall, the joints in the pipe being caulked withoakum saturated in cement, and pointed with cement mortar above a line1 in. Below the horizontal diameter, the remainder of each joint beingleft open. Cross-drains were laid from tees in the back drain to theface of the wall at all low points in the rock and at least for every25 ft. Of wall length, the joints of these discharge pipes being caulkedand cemented throughout. The surface of the rock was then washed andscraped clean, and was covered with about 1 in. Of mortar, after whichthe section was ready for concrete. The building of monolithic sections in trenches required that the thrustfrom one set of struts be taken by the concrete before the set abovecould be removed, and necessarily caused slow progress, the rate atwhich concrete was deposited being just sufficient to prevent one layerfrom setting before the next layer above could be placed. The concrete used was mixed in the proportions of 1 part of cement to3 parts of sand and 6 parts of stone, in 2-bag batches, in ¾-yd. And1-yd. Ransome portable mixers mounted with air-driven engines on the sameframe. These mixers were placed at the surface, and were charged withbarrows, the correct quantities of sand and stone for each batch beingmeasured in rectangular boxes previous to loading the barrows. Theconcrete was discharged from the mixer into a hopper which divided intotwo chutes, only one of which was used at a time, the concrete beingshoveled from the bottom of the chutes to its final position. Facingmortar, 2 in. Thick, was deposited simultaneously with the concrete, andwas kept separate from it by a steel diaphragm until both were in place, when the diaphragm was removed and the two were spaded together. Thebottoms of the guide-planks were cut off just above the concrete as itprogressed, and, as soon as the wall had reached a strut at one end ofthe section, that strut was removed, the form was built up to the nextstrut, at front and back, and braced to the sheeting, so that, by thetime the entire length of the section had been carried up to the levelof the first line of struts, forms were ready at one end for thesucceeding layers. The layers of concrete never exceeded 8 in. Inheight, and at times there were slight delays in the concreting whilethe carpenters made ready the next lift of forms, but such delays wererarely long enough to permit the concrete to take its initial set. [Illustration: Fig. 7. SKETCH SHOWING FORMS FOR, AND METHOD OF, CONCRETING RETAINING WALLS IN TRENCH. ] After a section of concrete had firmly set, both back and front formswere removed, and the thrust from the sides of the trench wastransferred directly to the finished wall. The face of the wall wasrubbed with a cement brick to remove the marks of the plank, and wasthen coated with a wash of thin cement grout. The water-proofing andbrick armor were then continued up the back of the wall, the spacesbetween the lines of braces being first water-proofed and bricked, andthe braces transferred to the finished surface, after which the omittedpanels were completed. The water-proofing consisted of three layers ofHydrex felt, of a brand known as Pennsylvania Special, and four layersof coal-tar pitch. The pitch contained not less than 25% of carbon, softened at 60° Fahr. , and melted at a point between 96° and 106° Fahr. The melting point was determined by placing 1 gramme of pitch on a leaddisk over a hole, 5/16-in. In diameter, and immersed in water which washeated at the rate of 1° per min. ; the temperature of the water at thetime the pitch ran through the hole was considered as the melting point. In order to prevent the water-proofing from being torn at the jointbetween sections when they contract from changes in temperature, avertical strip of felt, 6 in. Wide, was pitched over each joint, lapping3 in. On each concrete section. The back of this strip was not pitched, but was covered with pulverized soapstone, so that the water-proofingsheet was free from the wall for a distance of 3 in. On either side ofeach joint. Concreting was continued during the severest weather, one section beingplaced when the thermometer was 5° above zero. When the thermometer wasbelow the freezing point both sand and stone were heated by wood firesin large pipes under the supply piles; the temperature of the mix wastaken frequently, and was kept above 40 degrees. Numerous tests madewhile the work was in progress showed that, while the temperature fellslightly soon after the concrete was deposited, it was always from 2° to5° higher at the end of 2 hours. The face and back of the concrete wereprevented from freezing by a liberal packing of salt hay just outsidethe forms. A vertical hog trough, 24 in. Wide and 9 in. Deep, was placed in oneend of each section, for its full height below the bridge seat, intowhich the next section keyed, and, when the temperature at the timeof concreting was below 50° Fahr. , a compression joint was formed byplacing a strip of heavy deadening felt, 2 ft. Wide, on the end of thecompleted section next to the face and covering the remainder of theend with two ply of the felt and pitch water-proofing; the one ply ofdeadening felt near the face was about the same thickness as the two plyof water-proofing, and was used to prevent the pitch from being squeezedout of the joint to the face of the wall. The excavation for the retaining walls in 31st and 33d Streets were inall cases made of sufficient width to receive the sewers, which werelaid as soon as the back-fill, carefully rammed and puddled, had reachedthe proper elevations; the back-filling was then completed, and the gasand water mains were afterward laid in separate trenches. [Illustration: Fig. 8. SKETCH SHOWING FORMS AND BRACING FOR NINTH AVENUE WALL] The sections of concrete built in trench varied in height from 13 to59 ft. From the base to the top of the back wall. With the exception ofthe Seventh Avenue wall, 50 ft. In height, and the Ninth Avenue wall, 62 ft. In height, none of those sections constructed by the benchmethod was more than 14 ft. The forms and bracing for these walls weresubstantially the same, except that the low walls were built in lengthsof approximately 50 ft. , while the forms for the Seventh and NinthAvenue walls were only 20 ft. Long. The forms and bracing for the Ninth Avenue walls are shown on Fig. 8. These forms were built in one piece and moved ahead from section tosection, and they were firmly braced from the bottom with raker bracesto a point 36 ft. Above the base, the upper part being held in place by¾-in. Bolts passed through the forms and anchored by cables to boltsgrouted into the rock behind. After the forms had been set and braced, an 8-in. Brick wall was laidup the face of the rock, containing a vertical line of three-cell hollowtile block every 5 ft. Of length, and laid to conform as nearly aspossible to the face of the rock, all voids being filled with brokenstone. Water-proofing, similar to that described for the walls in thetrench, was then applied to the brick and tile wall for the full height, and firmly braced to the front forms, the braces being removed as theconcrete reached them. The concrete was mixed at the street level anddeposited through chutes, as described previously. Tables 1, 2, and 3 show the quantity of cement used in each section ofretaining wall, and give figures by which the quantities of othermaterials may be determined. _Pit Excavation. _--The pit excavation during the horse-and-truck periodwas largely preparatory work done to get the excavation in good shapefor handling spoil trains after Pier No. 72 and the trestle approachwere finished. This required an open cut from Ninth to Seventh Avenuesat a sufficient depth below the sewers and other substructures in theavenues to clear a locomotive, and wide enough for both running andloading tracks, also the building of the cast-iron sewer in EighthAvenue across the entire excavation, with enough of the temporarybridging to support it. The building of the trestle in Eighth Avenuewas essentially a part of the pit excavation, as the progress of onedepended greatly on that of the other. Excavation was commenced on July 12th, 1904, for the crossing underNinth Avenue, and in the pit east of Ninth Avenue along 32d Street. Theline chosen for the opening cut was down the center of the pit, as itwas not safe to excavate near the bounding streets until after thecompletion of the enclosing retaining wall. The excavation was startedby hand, but three 70-ton Bucyrus steam shovels were put to work as soonas they could be delivered, the first on July 25th and the third onSeptember 12th. The excavated material was loaded by the shovels onend-dump wagons, each having a capacity of 2 cu. Yd. , and was conveyedin them to the dumping board at 35th Street. The average number of teamswas 135, 10% being snatch teams to pull the wagons out of the pit and toassist them up the runway at the dumping board. The teams averaged onlyseven trips per day of 10 hours, considerable delay being caused by thetrains of the New York Central Railroad at Eleventh Avenue. The numberof teams was not sufficient, therefore, to keep the three shovels busywhen they were all in good digging, but the dumping board was taxed toaccommodate that number, and little would have been gained by increasingit. The digging was very good during this period, practically no rockbeing encountered, and the building foundations were too light topresent any obstacle to such powerful shovels. The capacity of theirdippers was 3½ cu. Yd. , so that one dipperful meant one truck loaded andrunning over. The output from August to November, inclusive, averaged40, 000 cu. Yd. Per month; one shift only was worked per day, andalthough the quantity was not large for three such powerful shovels, itwas large to truck through the streets, and required that one team passa given point every 18 sec. At the end of November the opening up ofthe pit had been accomplished, considerable rock had been strippednear Ninth Avenue, and the streets had become so icy that the cost oftransportation was practically doubled; work in the pit, therefore, wasmuch curtailed, and amounted to continuous work for one shovel from thattime until the end of the period, May 22d, 1905, when Pier No. 72 wasput in service and transportation by train began. Figs. 2 and 3, PlateLVI, show the condition of the pit east and west of Eighth Avenue, respectively, on that date. [Illustration: Fig. 9. SKETCH SHOWING TYPICAL BENT OF TRESTLE SUPPORTING EIGHTH AVENUE] The work of excavating for and building the temporary street bridge, a typical bent and bracing for which are shown on Fig. 9, and thecast-iron sewer and water mains in Eighth Avenue, was commenced onSeptember 3d, 1904. The trestle was a double-decked structure of yellowpine, with 10 by 10-in. Posts and sills, 10 by 14-in. Intermediate andtop caps, and 2 by 10-in. Longitudinal and cross-braces. The trestle wasfurther stiffened longitudinally by four lines of 8 by 10-in. Struts, butted between the intermediate caps, and held in position by 2 by 8-in. Splice-plates resting on top of them. The intermediate caps were at anelevation of 15 ft. Below the surface of the street, and above that linethe longitudinal bracing was continuous, while below it the bents werebraced in pairs, the bracing being omitted from every second bay. Belowthe intermediate cap the bents were uniform for the entire width of thetrestle, but the top cap was not continuous, being 5 ft. Below thesurface under the trolley tracks, and only 18 in. , the depth ofstringers and planking, beyond. The stringers under the trolley trackswere 8 by 16-in. Yellow pine, spaced three to a track, and those for thedriveway were 6 by 14-in. , spaced 1 ft. 6 in. On centers, the plankingbeing 4-in. Yellow pine. The first step in the construction was to excavate a trench 15 ft. Wideon the west side of the street, the east side of the trench being 4 ft. West of the westernmost trolley rail. While this work was in progress, all vehicular traffic was turned to that part of the avenue east of thewesterly trolley rail. The trench was sheeted and timbered, and carriedto a depth sufficient to receive the intermediate cap. That portion ofthe bent from the bottom of the intermediate cap to the bottom of thetop cap was then erected for the width of the trench, after which the60-in. Cast-iron sewer and the 48-in. Water main were laid in positionand caulked. The top cap, stringers, and planking were then laid, forthe full width of the trestle west of the trolley tracks. This work wasfinished and the sewage turned into the new sewer in April, 1905. As the planking was laid west of the trolley tracks, traffic was turnedto that side of the street, and the material east of the tracks wasexcavated to its natural slope. Trenches were then dug under the trackson the line of the bents, and the caps were set in position on blocking. The material between these trenches was then removed, the tracks beingsupported meanwhile by blocking at least every 6 ft. , and the stringersand planking were shoved into place. Excavation was next made betweenthe caps to a depth of about 5 ft. Below them, needle-beams being placedunder the caps, one or two at a time, and supported on posts erected inthese excavations; the material on line of the bents was excavated tothe depth of the intermediate caps, which were then set, togetherwith the posts and bracing for the upper deck of the structure. Thisoperation was repeated for the lower deck, about 10 ft. Being gained foreach change of posts, and three shifts, therefore, were required. At the beginning of the train-transportation period, May 22d, 1905, twoshifts of 10 hours each were inaugurated, and the earth was handled atthe rate of from 85, 000 to 90, 000 cu. Yd. Per month; but, by the end ofAugust, when a little more than 60% of the total earth had been disposedof, the rock began to interfere very greatly with the progress. Thestrike of the rock was almost directly north and south, and its surfaceformed broken ridges running in that direction, with deep valleysbetween. The dip was almost vertical near Ninth Avenue, and about 70°toward the west near Seventh Avenue. This condition made it necessary toturn the shovels parallel to the ridges in order to strip the rock fordrilling; and, as the ridges were very broken, the shovels continued tobump into them on all occasions, making it necessary to move back andstart other cuts or stand and wait for the rock to be drilled andblasted. One small Vulcan steam shovel, with vertical boiler and ¾-cu. Yd. Dipper, had been brought on the work to be used in stripping rock, and was moved from place to place so much more easily than the largeones that an Ohio shovel of the same general type was purchased inOctober, and thereafter the stripping was done largely by the two smallshovels and by hand, the large shovels being used almost exclusively inhandling rock. The drilling necessary to remove the rock was very large in amount andalso per yard excavated. In order not to damage the retaining walls andthe rock underlying them, holes spaced at 5-in. Centers were drilled1 ft. Away from the face of the walls and on the same batter. Thesebreaking holes alone amounted to a total of 210, 000 lin. Ft. , or 1 ft. Of hole for each 3½ cu. Yd. Of rock excavated; and the regulations ofthe Bureau of Combustibles, which prevented springing, caused theblasting holes to be placed very close together and required a total ofabout 420, 000 lin. Ft. , making 630, 000 ft. If to this is added the blockholes, for some of the rock broke very large, it will show at least1 ft. Of drill hole for each cubic yard of rock excavated, about tentimes the average on general railroad work. [Transcriber's Note: The three numbered Tables were originally printed at full width, with columns (1)-(13) displayed in a single row. ] TABLE 1a. --Record of Retaining-Wall Sections, Terminal Station. West Thirty-first Street from Seventh Avenue to Ninth Avenue. (1) Section No. (2) Stations. (3) Contents of section, in cubic yards. (4) Barrels of cement used for facing. (5) Cubic yards of facing mortar equivalent. (6) Barrels of cement used for bed mortar. (7) Cubic yards of bed mortar equivalent. (8) Cubic yards of embedded stone. (1) (2) (3) (4) (5) (6) (7) (8) _____________________________________________________________________ | 1 {165 + 05. 8} | | | | | | | | {165 + 66. 0} | 617. 48 | 17. 50 | 5. 95 | . .. | . .. | . .. | | 2 {165 + 66. 0} | | | | | | | | {165 + 95. 4} | 233. 96 | 10. 25 | 3. 49 | . .. | . .. | . .. | | 3 {165 + 95. 4} | | | | | | | | {166 + 41. 2} | 355. 20 | 24. 50 | 8. 34 | . .. | . .. | . .. | | 4 {171 + 03. 4} | | | | | | | | {171 + 53. 4} | 309. 29 | 67. 50 | 23. 00 | . .. | . .. | . .. | | 5 {177 + 44. 0} | | | | | | | | {177 + 94. 0} | 109. 62 | 30. 25 | 10. 30 | . .. | . .. | . .. | | 6 {171 + 53. 4} | | | | | | | | {171 + 83. 0} | 246. 35 | 27. 75 | 9. 44 | . .. | . .. | . .. | | 7 {166 + 41. 2} | | | | | | | | {166 + 79. 0} | 644. 12 | 77. 50 | 26. 37 | . .. | . .. | . .. | | 8 {171 + 83. 0} | | | | | | | | {172 + 12. 0} | 394. 43 | 63. 75 | 21. 69 | . .. | . .. | . .. | | 9 {166 + 79. 0} | | | | | | | | {167 + 20. 5} | 974. 58 |103. 75 | 35. 30 | 2. 50 | 0. 85 | 7. 96 | | 10 {170 + 16. 6} | | | | | | | | {170 + 58. 6} | 767. 34 | 92. 50 | 31. 48 | 2. 75 | 0. 94 | . .. | | 11 {170 + 58. 6} | | | | | | | | {171 + 03. 4} | 599. 17 | 77. 00 | 26. 20 | 10. 25 | 3. 49 | . .. | | 12 {167 + 20. 5} | | | | | | | | {167 + 43. 9} | 535. 28 | 50. 50 | 17. 18 | 2. 00 | 0. 68 | 4. 00 | | 13 {175 + 18. 5} | | | | | | | | {175 + 61. 8} | 553. 04 | 62. 00 | 21. 10 | 5. 25 | 1. 79 | . .. | | 14 {177 + 02. 9} | | | | | | | | {177 + 44. 0} | 305. 12 | 49. 25 | 16. 76 | 4. 50 | 1. 53 | . .. | | 15 {175 + 61. 8} | | | | | | | | {176 + 91. 7} | 429. 88 | 50. 00 | 17. 01 | 1. 50 | 0. 51 | . .. | | 16 {176 + 62. 5} | | | | | | | | {177 + 02. 9} | 675. 64 | 77. 50 | 26. 37 | 6. 25 | 2. 13 | . .. | | 17 {174 + 04. 5} | | | | | | | | {174 + 29. 6} | 162. 98 | 29. 00 | 9. 87 | 3. 50 | 1. 19 | . .. | | 18 {175 + 91. 7} | | | | | | | | {176 + 21. 5} | 698. 88 | 46. 25 | 15. 72 | 4. 50 | 1. 53 | 15. 86 | | 19 {176 + 21. 5} | | | | | | | | {176 + 62. 5} | 1, 166. 79 | 81. 50 | 27. 73 | 4. 00 | 1. 36 | 34. 96 | | 20 {167 + 43. 9} | | | | | | | | {167 + 92. 6} | 975. 53 | 95. 75 | 32. 58 | 3. 25 | 1. 11 | 36. 99 | | 21 {172 + 12. 0} | | | | | | | | {172 + 45. 2} | 271. 48 | 31. 75 | 10. 80 | 2. 50 | 0. 85 | 8. 65 | | 22 {168 + 41. 3} | | | | | | | | {168 + 72. 6} | 316. 30 | 44. 00 | 14. 97 | 5. 25 | 1. 79 | 7. 18 | | 23 {173 + 63. 6} | | | | | | | | {174 + 04. 5} | 529. 33 | 54. 75 | 18. 63 | 4. 75 | 1. 62 | 1. 25 | | 24 {167 + 92. 6} | | | | | | | | {168 + 41. 3} | 1, 010. 64 | 66. 00 | 22. 46 | 5. 50 | 1. 87 | 10. 16 | | 25 {173 + 21. 2} | | | | | | | | {173 + 63. 6} | 675. 21 | 77. 75 | 26. 46 | 2. 50 | 0. 85 | 12. 00 | | 26 {164 + 72. 5} | | | | | | | | {165 + 05. 8} | 458. 22 | 40. 00 | 13. 61 | 5. 50 | 1. 87 | 22. 37 | | 27 {172 + 81. 9} | | | | | | | | {173 + 21. 2} | 409. 43 | 35. 00 | 11. 91 | 9. 75 | 3. 31 | 4. 64 | | 28 {164 + 27. 6} | | | | | | | | {164 + 72. 5} | 658. 46 | 72. 00 | 24. 50 | 1. 50 | 0. 51 | 16. 40 | | 29 {172 + 45. 2} | | | | | | | | {172 + 81. 9} | 345. 89 | 30. 25 | 10. 29 | 5. 00 | 1. 70 | 1. 62 | | 31 {174 + 78. 0} | | | | | | | | {175 + 18. 5} | 507. 50 | 35. 75 | 12. 17 | 3. 00 | 1. 02 | 17. 09 | | 32 {174 + 29. 6} | | | | | | | | {174 + 78. 0} | 396. 99 | 43. 75 | 14. 89 | 1. 75 | 0. 60 | 6. 50 | | 43 {177 + 94. 0} | | | | | | | | {178 + 44. 1} | 194. 07 | 30. 00 | 10. 21 | 2. 00 | 0. 68 | 8. 35 | | Pier {168 + 72. 6} | | | | | | | | {168 + 81. 1} | 106. 52 | . .. | . .. | . .. | . .. | . .. | | 76 {178 + 44. 1} | | | | | | | | {178 + 94. 1} | 136. 32 | 12. 75 | 4. 34 | 4. 75 | 1. 62 | . .. | | 79 {178 + 94. 1} | | | | | | | | {179 + 44. 1} | 118. 07 | 9. 00 | 3. 06 | 8. 50 | 1. 19 | . .. | | 82 {179 + 44. 1} | | | | | | | | {179 + 93. 7} | 126. 12 | 6. 50 | 2. 21 | 2. 50 | 0. 85 | . .. | | 84 {179 + 93. 7} | | | | | | | | {180 + 44. 2} | 126. 77 | 6. 75 | 2. 30 | 2. 25 | 0. 77 | . .. | | 86 {180 + 44. 2} | | | | | | | | {180 + 93. 6} | 162. 48 | 8. 00 | 2. 72 | 2. 75 | 0. 94 | . .. | | 90 {180 + 93. 6} | | | | | | | | {181 + 17. 9} | 92. 52 | 4. 00 | 1. 36 | 1. 00 | 0. 34 | . .. | |___________________|__________|_______|_______|_______|______|_______| TABLE 1b. --Record of Retaining-Wall Sections, Terminal Station. West Thirty-first Street from Seventh Avenue to Ninth Avenue. (1) Section No. (2) Stations. (9) Cubic yards of concrete in section (net). (10) Barrels of cement used in concrete. (11) Barrels of cement per cubic yard of concrete. (12) Concrete started. (13) Concrete finished. (1) (2) (9) (10) (11) (12) (13) ______________________________________________________________________ | 1 {165 + 05. 8} | | | | | | | {165 + 66. 0} | 611. 53 | 731. 50 | 1. 20 | 11/4/04 | 11/20/04 | | 2 {165 + 66. 0} | | | | | | | {165 + 95. 4} | 230. 47 | 277. 25 | 1. 20 | 11/21/04 | 11/27/04 | | 3 {165 + 95. 4} | | | | | | | {166 + 41. 2} | 346. 86 | 398. 25 | 1. 15 | 11/26/04 | 12/3/04 | | 4 {171 + 03. 4} | | | | | | | {171 + 53. 4} | 286. 29 | 360. 50 | 1. 26 | 12/2/04 | 12/10/04 | | 5 {177 + 44. 0} | | | | | | | {177 + 94. 0} | 99. 32 | 120. 75 | 1. 22 | 12/28/04 | 12/30/04 | | 6 {171 + 53. 4} | | | | | | | {171 + 83. 0} | 236. 91 | 292. 50 | 1. 23 | 1/2/05 | 1/11/05 | | 7 {166 + 41. 2} | | | | | | | {166 + 79. 0} | 617. 75 | 737. 00 | 1. 19 | 1/13/05 | 2/4/05 | | 8 {171 + 83. 0} | | | | | | | {172 + 12. 0} | 372. 74 | 420. 75 | 1. 13 | 1/14/05 | 1/28/05 | | 9 {166 + 79. 0} | | | | | | | {167 + 20. 5} | 930. 47 | 1, 066. 25 | 1. 14 | 2/18/05 | 3/13/05 | | 10 {170 + 16. 6} | | | | | | | {170 + 58. 6} | 734. 92 | 852. 50 | 1. 16 | 1/31/05 | 2/25/05 | | 11 {170 + 58. 6} | | | | | | | {171 + 03. 4} | 569. 48 | 689. 75 | 1. 21 | 3/11/05 | 3/23/05 | | 12 {167 + 20. 5} | | | | | | | {167 + 43. 9} | 513. 42 | 611. 75 | 1. 19 | 3/9/05 | 3/26/05 | | 13 {175 + 18. 5} | | | | | | | {175 + 61. 8} | 530. 15 | 630. 50 | 1. 19 | 3/15/05 | 3/29/05 | | 14 {177 + 02. 9} | | | | | | | {177 + 44. 0} | 286. 83 | 340. 25 | 1. 19 | 3/26/05 | 3/31/05 | | 15 {175 + 61. 8} | | | | | | | {176 + 91. 7} | 412. 36 | 472. 50 | 1. 15 | 3/28/05 | 4/14/05 | | 16 {176 + 62. 5} | | | | | | | {177 + 02. 9} | 647. 14 | 788. 00 | 1. 22 | 4/1/05 | 4/17/05 | | 17 {174 + 04. 5} | | | | | | | {174 + 29. 6} | 151. 92 | 182. 50 | 1. 20 | 5/3/05 | 5/6/05 | | 18 {175 + 91. 7} | | | | | | | {176 + 21. 5} | 665. 77 | 801. 00 | 1. 20 | 5/9/05 | 5/19/05 | | 19 {176 + 21. 5} | | | | | | | {176 + 62. 5} | 1, 102. 74 | 1, 354. 50 | 1. 23 | 5/15/05 | 5/28/05 | | 20 {167 + 43. 9} | | | | | | | {167 + 92. 6} | 904. 85 | 1, 012. 75 | 1. 12 | 5/25/05 | 6/3/05 | | 21 {172 + 12. 0} | | | | | | | {172 + 45. 2} | 251. 18 | 311. 50 | 1. 24 | 5/29/05 | 6/3/05 | | 22 {168 + 41. 3} | | | | | | | {168 + 72. 6} | 292. 36 | 338. 75 | 1. 16 | 6/5/05 | 6/10/05 | | 23 {173 + 63. 6} | | | | | | | {174 + 04. 5} | 507. 83 | 587. 25 | 1. 16 | 6/5/05 | 6/13/05 | | 24 {167 + 92. 6} | | | | | | | {168 + 41. 3} | 976. 15 | 1, 038. 75 | 1. 07 | 6/8/05 | 6/21/05 | | 25 {173 + 21. 2} | | | | | | | {173 + 63. 6} | 635. 90 | 776. 25 | 1. 22 | 6/16/05 | 6/24/05 | | 26 {164 + 72. 5} | | | | | | | {165 + 05. 8} | 420. 37 | 532. 00 | 1. 26 | 6/23/05 | 6/28/05 | | 27 {172 + 81. 9} | | | | | | | {173 + 21. 2} | 389. 57 | 450. 00 | 1. 16 | 6/27/05 | 7/7/05 | | 28 {164 + 27. 6} | | | | | | | {164 + 72. 5} | 617. 05 | 726. 25 | 1. 18 | 6/29/05 | 7/7/05 | | 29 {172 + 45. 2} | | | | | | | {172 + 81. 9} | 332. 28 | 384. 00 | 1. 16 | 7/11/05 | 7/19/05 | | 31 {174 + 78. 0} | | | | | | | {175 + 18. 5} | 477. 22 | 567. 50 | 1. 19 | 7/29/05 | 8/6/05 | | 32 {174 + 29. 6} | | | | | | | {174 + 78. 0} | 375. 00 | 434. 25 | 1. 16 | 8/5/05 | 8/12/05 | | 43 {177 + 94. 0} | | | | | | | {178 + 44. 1} | 174. 83 | 219. 75 | 1. 26 | 11/9/05 | 11/12/05 | | Pier {168 + 72. 6} | | | | | | | {168 + 81. 1} | 106. 52 | 144. 00 | 1. 35 | 12/6/06 | 12/8/06 | | 76 {178 + 44. 1} | | | | | | | {178 + 94. 1} | 130. 36 | 142. 50 | 1. 09 | 7/8/07 | 7/10/07 | | 79 {178 + 94. 1} | | | | | | | {179 + 44. 1} | 113. 82 | 129. 50 | 1. 14 | 7/15/07 | 7/16/07 | | 82 {179 + 44. 1} | | | | | | | {179 + 93. 7} | 123. 06 | 131. 75 | 1. 07 | 7/22/07 | 7/23/07 | | 84 {179 + 93. 7} | | | | | | | {180 + 44. 2} | 123. 70 | 133. 50 | 1. 08 | 7/26/07 | 7/27/07 | | 86 {180 + 44. 2} | | | | | | | {180 + 93. 6} | 158. 82 | 167. 00 | 1. 05 | 7/30/07 | 7/31/07 | | 90 {180 + 93. 6} | | | | | | | {181 + 17. 9} | 90. 82 | 115. 00 | 1. 27 | 8/18/08 | 8/18/08 | |___________________|__________|__________|______|__________|__________| NOTE. --The number of cubic yards of crushed stone used in any sectioncan be found by multiplying the figure for that section in Column 10 by0. 7778. The number of cubic yards of sand used in any section can be found bymultiplying: the sum of the figures for that section in Columns 4, 6, and 10 by 0. 3889. REMARKS. --Section No. 4. Amount of sand cut down on a part of this section on account of dust in stone. Section No. 8. O'Rourke stone used on this section, large and full of dust. Section No. 9. Stone crushed on the work used on this section, large and full of dust. Section No. 21. 1:3:5 mix was used in part of this section on account of stone being large. Section No. 24. Different sized stone was shipped on barge and mixed on the board for this section. Section No. 25. 1:3:5 mix used in a small part of this section on account of stone being large. Sections Nos. 76, 82, 84, and 86. Stone contained large amount of dust. TABLE 2a. --Record of Retaining-wall Sections, Terminal Station. West Thirty-third Street from Seventh Avenue to Ninth Avenue. (1) Section No. (2) Stations. (3) Contents of section, in cubic yards. (4) Barrels of cement used for facing. (5) Cubic yards of facing mortar equivalent. (6) Barrels of cement used for bed mortar. (7) Cubic yards of bed mortar equivalent. (8) Cubic yards of embedded stone. (1) (2) (3) (4) (5) (6) (7) (8) ___________________________________________________________________ | 30 {170 + 73. 2} | | | | | | | | {171 + 16. 1} | 364. 72 | 42. 50 | 14. 46 | 4. 00 | 1. 36 | . .. | | 33 {178 + 48. 7} | | | | | | | | {178 + 84. 1} | 180. 40 | 29. 50 | 10. 04 | 3. 50 | 1. 19 | . .. | | 34 {R 2 + 75. 5} | | | | | | | | {170 + 03. 5} | 214. 12 | 38. 00 | 12. 93 | 1. 00 | 0. 34 | 1. 50 | | 35 {171 + 16. 1} | | | | | | | | {171 + 42. 5} | 381. 56 | 40. 25 | 13. 70 | 1. 00 | 0. 34 | 14. 37 | | 36 {170 + 03. 6} | | | | | | | | {170 + 25. 0} | 150. 16 | 20. 50 | 6. 98 | . .. | . .. | 6. 25 | | 37 {171 + 42. 5} | | | | | | | | {171 + 91. 3} | 869. 40 | 59. 50 | 20. 25 | 4. 50 | 1. 53 | 44. 96 | | 38 {171 + 91. 3} | | | | | | | | {172 + 19. 2} | 233. 49 | 22. 75 | 7. 74 | 2. 75 | 0. 94 | 14. 45 | | 39 {179 + 27. 2} | | | | | | | | {179 + 64. 2} | 255. 39 | 32. 00 | 10. 89 | 3. 00 | 1. 02 | 9. 05 | | 40 {170 + 25. 0} | | | | | | | | {170 + 73. 2} | 500. 73 | 44. 25 | 15. 06 | 1. 00 | 0. 34 | 29. 64 | | 41 {169 + 50. 8} | | | | | | | | {R 2 + 75. 5} | 215. 93 | 28. 25 | 9. 61 | 2. 00 | 0. 68 | . .. | | 42 {178 + 84. 1} | | | | | | | | {179 + 27. 2} | 177. 62 | 23. 00 | 7. 83 | 1. 50 | 0. 51 | 7. 06 | | 44 {180 + 05. 5} | | | | | | | | {180 + 44. 2} | 936. 15 | 58. 75 | 19. 99 | 10. 50 | 3. 47 | 73. 84 | | 45 {180 + 44. 2} | | | | | | | | {180 + 74. 9} | 1, 133. 59 | 60. 00 | 20. 42 | 5. 00 | 1. 70 | 60. 71 | | 46 {179 + 64. 2} | | | | | | | | {180 + 05. 5} | 477. 14 | 35. 00 | 11. 91 | 3. 75 | 1. 28 | 24. 58 | | 47 {169 + 00. 1} | | | | | | | | {169 + 50. 8} | 136. 19 | 14. 25 | 4. 85 | 3. 50 | 1. 19 | 2. 00 | | 48 {178 + 24. 1} | | | | | | | | {178 + 48. 7} | 192. 78 | 21. 25 | 7. 23 | 2. 00 | 0. 68 | . .. | | 49 {177 + 81. 1} | | | | | | | | {178 + 24. 1} | 241. 51 | 25. 25 | 8. 59 | 2. 50 | 0. 85 | 1. 33 | | 50 {168 + 03. 6} | | | | | | | | {168 + 45. 6} | 405. 61 | 25. 50 | 8. 68 | 4. 00 | 1. 36 | 36. 10 | | 51 {177 + 38. 4} | | | | | | | | {177 + 81. 1} | 100. 54 | 12. 75 | 4. 34 | 3. 00 | 1. 02 | 0. 78 | | 52 {168 + 45. 6} | | | | | | | | {168 + 80. 1} | 181. 96 | 19. 00 | 6. 47 | 1. 00 | 0. 34 | 9. 03 | | 53 {168 + 80. 1} | | | | | | | | {169 + 00. 1} | 41. 32 | 3. 50 | 1. 19 | . .. | . .. | . .. | | 55 {176 + 90. 0} | | | | | | | | {177 + 38. 4} | 92. 41 | 11. 25 | 3. 83 | 2. 50 | 0. 85 | 3. 68 | | 56 {167 + 62. 1} | | | | | | | | {168 + 03. 6} | 383. 67 | 33. 75 | 11. 48 | 3. 25 | 1. 11 | 36. 62 | | 59 {175 + 67. 3} | | | | | | | | {175 + 98. 9} | 175. 61 | 15. 50 | 5. 27 | 2. 50 | 0. 85 | 9. 37 | | 60 {176 + 49. 0} | | | | | | | | {176 + 90. 0} | 69. 97 | 8. 25 | 2. 81 | 3. 00 | 1. 02 | 1. 58 | | 61 {175 + 98. 9} | | | | | | | | {176 + 49. 0} | 104. 56 | 8. 00 | 2. 72 | 3. 50 | 1. 19 | 3. 72 | | 64 {175 + 30. 3} | | | | | | | | {175 + 67. 3} | 140. 15 | 14. 75 | 5. 02 | 2. 75 | 0. 94 | . .. | | 65 {174 + 85. 4} | | | | | | | | {175 + 30. 3} | 80. 66 | 9. 00 | 3. 06 | 2. 50 | 0. 85 | . .. | | 66 {174 + 47. 9} | | | | | | | | {174 + 85. 4} | 68. 89 | 5. 50 | 1. 87 | 3. 25 | 1. 11 | . .. | | 67 {174 + 21. 1} | | | | | | | | {174 + 47. 9} | 60. 14 | 3. 00 | 1. 02 | 2. 00 | 0. 68 | 0. 92 | | 68 {167 + 12. 3} | | | | | | | | {167 + 62. 1} | 379. 94 | 23. 50 | 8. 00 | 5. 00 | 1. 70 | 19. 34 | | 69 {173 + 85. 6} | | | | | | | | {174 + 21. 1} | 77. 43 | 6. 50 | 2. 21 | 3. 00 | 1. 02 | . .. | | 70 {166 + 75. 6} | | | | | | | | {167 + 12. 3} | 408. 81 | 33. 75 | 11. 48 | 3. 75 | 1. 28 | . .. | | 71 {173 + 46. 5} | | | | | | | | {173 + 85. 6} | 85. 92 | 8. 25 | 2. 81 | 1. 75 | 0. 60 | . .. | | 74 {172 + 19. 2} | | | | | | | | {172 + 73. 0} | 449. 28 | 22. 75 | 7. 74 | 6. 25 | 2. 13 | . .. | | 75 {172 + 73. 0} | | | | | | | | {173 + 24. 0} | 502. 20 | 27. 25 | 9. 27 | 7. 00 | 2. 38 | . .. | | 77 {164 + 77. 0} | | | | | | | | {165 + 27. 1} | 141. 38 | 9. 00 | 3. 06 | 7. 25 | 2. 47 | . .. | | 78 {168 + 83. 4} | | | | | | | | {169 + 18. 3} | 63. 35 | 3. 00 | 1. 02 | 1. 50 | 0. 51 | . .. | | 80 {165 + 27. 1} | | | | | | | | {165 + 76. 6} | 108. 86 | 11. 75 | 4. 00 | 3. 00 | 1. 02 | . .. | | 81 {168 + 45. 6} | | | | | | | | {168 + 83. 4} | 210. 97 | 13. 00 | 4. 42 | 6. 25 | 2. 13 | . .. | | 83 {165 + 76. 6} | | | | | | | | {166 + 20. 5} | 108. 06 | 8. 00 | 2. 72 | 3. 75 | 1. 28 | . .. | | 85 {166 + 20. 5} | | | | | | | | {166 + 64. 6} | 107. 52 | 9. 00 | 3. 06 | 2. 25 | 0. 76 | . .. | | 87 {166 + 64. 6} | | | | | | | | {166 + 75. 6} | 23. 44 | 1. 00 | 0. 34 | 2. 25 | 0. 42 | . .. | | 88 {164 + 26. 3} | | | | | | | | {164 + 77. 0} | 317. 72 | 24. 00 | 8. 17 | 2. 25 | 0. 76 | . .. | | 89 {173 + 20. 8} | | | | | | | | {173 + 46. 5} | 93. 51 | 5. 60 | 1. 70 | 1. 50 | 0. 51 | . .. | | 91 {180 + 74. 9} | | | | | | | | {180 + 92. 7} | 141. 40 | 17. 50 | 5. 96 | . .. | . .. | . .. | | 92 {180 + 92. 7} | | | | | | | | {181 + 28. 8} | 118. 93 | 19. 00 | 6. 46 | . .. | . .. | . .. | |_________________|__________|_______|_______|_______|______|_______| TABLE 2b. --Record of Retaining-wall Sections, Terminal Station. West Thirty-third Street from Seventh Avenue to Ninth Avenue. (1) Section No. (2) Stations. (9) Cubic yards of concrete in section (net). (10) Barrels of cement used in concrete. (11) Barrels of cement per cubic yard of concrete. (12) Concrete started. (13) Concrete finished. (1) (2) (9) (10) (11) (12) (13) ___________________________________________________________________ |30 {170 + 73. 2} | | | | | | | {171 + 16. 1} | 348. 90 | 391. 00 | 1. 12 | 7/20/05 | 7/26/05 | |33 {178 + 48. 7} | | | | | | | {178 + 84. 1} | 169. 17 | 188. 00 | 1. 11 | 8/7/05 | 8/11/05 | |34 {R 2 + 75. 5} | | | | | | | {170 + 03. 5} | 199. 35 | 217. 25 | 1. 09 | 8/14/05 | 8/19/05 | |35 {171 + 16. 1} | | | | | | | {171 + 42. 5} | 353. 15 | 400. 25 | 1. 13 | 8/16/05 | 8/22/05 | |36 {170 + 03. 6} | | | | | | | {170 + 25. 0} | 136. 93 | 133. 75 | 0. 98 | 8/19/05 | 8/22/05 | |37 {171 + 42. 5} | | | | | | | {171 + 91. 3} | 802. 66 | 909. 00 | 1. 13 | 8/22/05 | 9/6/05 | |38 {171 + 91. 3} | | | | | | | {172 + 19. 2} | 210. 36 | 238. 50 | 1. 13 | 8/24/05 | 8/27/05 | |39 {179 + 27. 2} | | | | | | | {179 + 64. 2} | 234. 43 | 270. 25 | 1. 15 | 8/29/05 | 9/2/05 | |40 {170 + 25. 0} | | | | | | | {170 + 73. 2} | 455. 69 | 525. 75 | 1. 15 | 9/11/05 | 9/15/05 | |41 {169 + 50. 8} | | | | | | | {R 2 + 75. 5} | 205. 64 | 236. 50 | 1. 15 | 10/3/05 | 10/6/05 | |42 {178 + 84. 1} | | | | | | | {179 + 27. 2} | 162. 22 | 194. 75 | 1. 20 | 10/9/05 | 10/11/05 | |44 {180 + 05. 5} | | | | | | | {180 + 44. 2} | 838. 85 | 987. 00 | 1. 18 | 11/17/05 | 11/27/05 | |45 {180 + 44. 2} | | | | | | | {180 + 74. 9} | 1, 050. 86 | 1, 206. 00 | 1. 15 | 12/13/05 | 12/23/05 | |46 {179 + 64. 2} | | | | | | | {180 + 05. 5} | 439. 37 | 535. 00 | 1. 22 | 1/15/06 | 1/19/06 | |47 {169 + 00. 1} | | | | | | | {169 + 50. 8} | 128. 15 | 150. 50 | 1. 17 | 4/4/06 | 4/6/06 | |48 {178 + 24. 1} | | | | | | | {178 + 48. 7} | 184. 87 | 226. 00 | 1. 22 | 4/24/06 | 4/30/06 | |49 {177 + 81. 1} | | | | | | | {178 + 24. 1} | 230. 74 | 274. 00 | 1. 19 | 5/21/06 | 5/24/06 | |50 {168 + 03. 6} | | | | | | | {168 + 45. 6} | 359. 47 | 406. 00 | 1. 13 | 6/13/06 | 6/18/06 | |51 {177 + 38. 4} | | | | | | | {177 + 81. 1} | 94. 40 | 112. 00 | 1. 19 | 6/20/06 | 6/21/06 | |52 {168 + 45. 6} | | | | | | | {168 + 80. 1} | 166. 12 | 190. 00 | 1. 14 | 6/25/06 | 6/28/06 | |53 {168 + 80. 1} | | | | | | | {169 + 00. 1} | 40. 13 | 44. 50 | 1. 11 | 6/29/06 | 6/29/06 | |55 {176 + 90. 0} | | | | | | | {177 + 38. 4} | 84. 05 | 98. 25 | 1. 17 | 8/17/06 | 8/18/06 | |56 {167 + 62. 1} | | | | | | | {168 + 03. 6} | 334. 46 | 383. 50 | 1. 14 | 8/28/06 | 9/1/06 | |59 {175 + 67. 3} | | | | | | | {175 + 98. 9} | 160. 12 | 186. 00 | 1. 16 | 10/15/06 | 10/16/06 | |60 {176 + 49. 0} | | | | | | | {176 + 90. 0} | 64. 56 | 75. 00 | 1. 16 | 10/17/06 | 10/18/06 | |61 {175 + 98. 9} | | | | | | | {176 + 49. 0} | 96. 93 | 108. 00 | 1. 11 | 10/19/06 | 10/20/06 | |64 {175 + 30. 3} | | | | | | | {175 + 67. 3} | 134. 19 | 161. 50 | 1. 20 | 11/21/06 | 11/22/06 | |65 {174 + 85. 4} | | | | | | | {175 + 30. 3} | 76. 75 | 92. 75 | 1. 21 | 12/14/06 | 12/15/06 | |66 {174 + 47. 9} | | | | | | | {174 + 85. 4} | 65. 91 | 83. 50 | 1. 27 | 12/18/06 | 12/18/06 | |67 {174 + 21. 1} | | | | | | | {174 + 47. 9} | 57. 52 | 67. 50 | 1. 17 | 12/21/06 | 12/21/06 | |68 {167 + 12. 3} | | | | | | | {167 + 62. 1} | 350. 90 | 412. 50 | 1. 17 | 1/2/07 | 1/6/07 | |69 {173 + 85. 6} | | | | | | | {174 + 21. 1} | 74. 20 | 91. 00 | 1. 23 | 1/29/07 | 1/30/07 | |70 {166 + 75. 6} | | | | | | | {167 + 12. 3} | 396. 05 | 468. 50 | 1. 18 | 4/2/07 | 4/10/07 | |71 {173 + 46. 5} | | | | | | | {173 + 85. 6} | 82. 51 | 95. 75 | 1. 16 | 4/17/07 | 4/19/07 | |74 {172 + 19. 2} | | | | | | | {172 + 73. 0} | 439. 41 | 506. 00 | 1. 15 | 6/20/07 | 6/24/07 | |75 {172 + 73. 0} | | | | | | | {173 + 24. 0} | 490. 55 | 579. 00 | 1. 18 | 7/8/07 | 8/25/07 | |77 {164 + 77. 0} | | | | | | | {165 + 27. 1} | 135. 85 | 161. 50 | 1. 19 | 7/13/07 | 7/15/07 | |78 {168 + 83. 4} | | | | | | | {169 + 18. 3} | 61. 82 | 73. 00 | 1. 18 | 7/13/07 | 7/14/07 | |80 {165 + 27. 1} | | | | | | | {165 + 76. 6} | 103. 84 | 133. 50 | 1. 28 | 7/18/07 | 7/19/07 | |81 {168 + 45. 6} | | | | | | | {168 + 83. 4} | 204. 42 | 255. 75 | 1. 25 | 7/20/07 | 7/23/07 | |83 {165 + 76. 6} | | | | | | | {166 + 20. 5} | 104. 06 | 128. 50 | 1. 23 | 7/25/07 | 7/27/07 | |85 {166 + 20. 5} | | | | | | | {166 + 64. 6} | 103. 70 | 144. 50 | 1. 39 | 7/29/07 | 7/30/07 | |87 {166 + 64. 6} | | | | | | | {166 + 75. 6} | 22. 68 | 30. 00 | 1. 32 | 7/31/07 | 7/31/07 | |88 {164 + 26. 3} | | | | | | | {164 + 77. 0} | 308. 79 | 370. 00 | 1. 20 | 8/8/07 | 8/11/07 | |89 {173 + 20. 8} | | | | | | | {173 + 46. 5} | 91. 30 | 121. 75 | 1. 33 | 9/7/07 | 9/8/07 | |91 {180 + 74. 9} | | | | | | | {180 + 92. 7} | 135. 44 | 203. 50 | 1. 50 | 11/18/07 | 11/20/0 | |92 {180 + 92. 7} | | | | | | | {181 + 28. 8} | 112. 47 | 190. 00 | 1. 69 | 12/1/08 | 12/2/08 | |________________|__________|__________|______|__________|__________| NOTE. --The number of cubic yards of crushed stone used in any sectioncan be found by multiplying the figure for that section in Column 10 by0. 7778. The number of cubic yards of sand used in any section can be found bymultiplying the sum of the figures for that section in Columns 4, 6, and10 by 0. 3889. REMARKS. --Section No. 47. Part of this section was removed on account of damage done by blasting and was replaced by Section No. 78. Section No. 52. All of this section was removed on account of damage done by blasting and was replaced by Section No. 81. Section No. 53. All of this section was removed on account of damage done by blasting and was replaced by Sections Nos. 78 and 81. TABLE 3a. --Record of Retaining Wall Sections. (1) Section No. (2) Stations. (3) Contents of section, in cubic yards. (4) Barrels of cement used for facing. (5) Cubic yards of facing mortar equivalent. (6) Barrels of cement used for bed mortar. (7) Cubic yards of bed mortar equivalent. (8) Cubic yards of embedded stone. Power-House. (1) (2) (3) (4) (5) (6) (7) (8) ________________________________________________________________ | A {L 2 + 75. 3} | | | | | | | | {L 3 + 25. 3} | 463. 28 | 58. 25 | 19. 82 | 5. 50 | 1. 87 | 11. 50 | | B {L 3 + 25. 3} | | | | | | | | {L 3 + 74. 9} | 114. 78 | 23. 00 | 7. 83 | 1. 75 | 0. 60 | 1. 50 | | C {169 + 30. 8} | | | | | | | | {169 + 74. 8} | 179. 19 | 34. 25 | 11. 66 | 1. 00 | 0. 34 | 3. 60 | | D {169 + 74. 8} | | | | | | | | {170 + 28. 8} | 114. 38 | 27. 25 | 9. 27 | 0. 25 | 0. 09 | 0. 07 | | E {168 + 83. 6} | | | | | | | | {169 + 30. 8} | 101. 20 | 22. 00 | 7. 49 | 1. 50 | 0. 51 | 0. 65 | | F {L 2 + 78. 2} | | | | | | | | {L 3 + 19. 6} | 358. 80 | 39. 50 | 13. 44 | 0. 75 | 0. 26 | 9. 50 | | G {L 3 + 19. 6} | | | | | | | | {L 3 + 56. 9} | 237. 33 | 23. 00 | 7. 83 | 1. 00 | 0. 34 | 0. 74 | | H {L 3 + 56. 9} | | | | | | | | {168 + 83. 5} | 25. 55 | 6. 25 | 2. 13 | 0. 75 | 0. 26 | . .. | |_________________|________|_______|_______|______|______|_______| Seventh Avenue. ________________________________________________________________ | 54 {164 + 27. 6} | | | | | | | | {L 2 + 32. 0} | 764. 48 | 69. 75 | 23. 74 | 3. 00 | 1. 02 | . .. | | 57 {L 2 + 10. 3} | | | | | | | | {L 2 + 32. 0} | 533. 06 | 34. 00 | 11. 57 | 2. 25 | 0. 77 | . .. | | 58 {L 1 + 87. 1} | | | | | | | | {L 2 + 10. 3} | 544. 54 | 32. 25 | 10. 97 | 2. 00 | 0. 68 | 9. 80 | | 62 {L 1 + 87. 1} | | | | | | | | {L 1 + 64. 4} | 575. 67 | 30. 00 | 10. 21 | 3. 00 | 1. 02 | 6. 20 | | 63 {L 1 + 42. 4} | | | | | | | | {L 1 + 64. 4} | 607. 01 | 30. 50 | 10. 38 | 2. 50 | 0. 85 | 3. 79 | | 72 {L 1 + 42. 4} | | | | | | | | {L 1 + 19. 6} | 631. 97 | 30. 00 | 10. 21 | 1. 75 | 0. 60 | 1. 18 | | 73 {L 1 + 19. 6} | | | | | | | | {L 0 + 97. 0} | 573. 33 | 25. 25 | 8. 59 | 0. 25 | 0. 08 | 2. 48 | |_________________|________|_______|_______|______|______|_______| TABLE 3b. --Record of Retaining Wall Sections. (1) Section No. (2) Stations. (9) Cubic yards of concrete in section (net). (10) Barrels of cement used in concrete. (11) Barrels of cement per cubic yard of concrete. (12) Concrete started. (13) Concrete finished. Power-House. (1) (2) (9) (10) (11) (12) (13) ________________________________________________________________ | A {L 2 + 75. 3} | | | | | | | {L 3 + 25. 3} | 430. 09 | 482. 75 | 1. 12 | 5/18/05 | 5/25/05 | | B {L 3 + 25. 3} | | | | | | | {L 3 + 74. 9} | 104. 85 | 125. 50 | 1. 20 | 6/14/05 | 6/16/05 | | C {169 + 30. 8} | | | | | | | {169 + 74. 8} | 163. 59 | 183. 00 | 1. 12 | 7/10/05 | 7/13/05 | | D {169 + 74. 8} | | | | | | | {170 + 28. 8} | 104. 95 | 119. 25 | 1. 14 | 7/14/05 | 7/19/05 | | E {168 + 83. 6} | | | | | | | {169 + 30. 8} | 92. 55 | 107. 25 | 1. 16 | 7/26/05 | 7/28/05 | | F {L 2 + 78. 2} | | | | | | | {L 3 + 19. 6} | 335. 60 | 397. 75 | 1. 18 | 9/19/05 | 9/24/05 | | G {L 3 + 19. 6} | | | | | | | {L 3 + 56. 9} | 228. 42 | 278. 00 | 1. 22 | 9/26/05 | 9/29/05 | | H {L 3 + 56. 9} | | | | | | | {168 + 83. 5} | 23. 16 | 28. 00 | 1. 21 | 9/29/05 | 9/29/05 | |_________________|________|________|______|__________|__________| Seventh Avenue. ________________________________________________________________ | 54 {164 + 27. 6} | | | | | | | {L 2 + 32. 0} | 739. 72 | 907. 50 | 1. 23 | 8/6/06 | 8/15/06 | | 57 {L 2 + 10. 3} | | | | | | | {L 2 + 32. 0} | 520. 72 | 610. 75 | 1. 17 | 9/10/06 | 9/15/06 | | 58 {L 1 + 87. 1} | | | | | | | {L 2 + 10. 3} | 523. 09 | 588. 25 | 1. 12 | 9/24/06 | 9/28/06 | | 62 {L 1 + 87. 1} | | | | | | | {L 1 + 64. 4} | 538. 24 | 639. 50 | 1. 19 | 10/24/06 | 10/29/06 | | 63 {L 1 + 42. 4} | | | | | | | {L 1 + 64. 4} | 581. 99 | 678. 50 | 1. 17 | 11/5/06 | 11/11/06 | | 72 {L 1 + 42. 4} | | | | | | | {L 1 + 19. 6} | 619. 98 | 719. 50 | 1. 16 | 4/25/07 | 4/30/07 | | 73 {L 1 + 19. 6} | | | | | | | {L 0 + 97. 0} | 562. 18 | 685. 75 | 1. 22 | 5/13/07 | 5/18/07 | |_________________|________|________|______|__________|__________| NOTE. --The number of cubic yards of crushed stone used in any sectioncan be found by multiplying the figure for that section in Column 10 by0. 7778. The number of cubic yards of sand used in any section can befound by multiplying the sum of the figures for that section in Columns4, 6, and 10 by 0. 3889. Channeling with a 10-ft quarry bar, carrying a No. 4 Ingersoll-Randdrill with Z-bits, was attempted in place of the close drilling belowthe walls, but, as the rock stood so nearly vertical and was full ofsoft seams, very little could be accomplished, the average cut per dayof 10 hours, counting the time of moving and setting up, was only 4 sq. Ft. , and, after a thorough trial, the bars were abandoned. _Disposal. _--The excavated material was hauled from the shovels to thepier in 10-car trains. The cars were of three classes: 4-yd. Westerndump-cars, flat cars without skips, and flats carrying speciallydesigned steel skips having a capacity of 4 cu. Yd. Each. As far aspracticable, earth, and rock containing 1 cu. Yd. Or less, was loadedon dumpers, medium-sized rock on the skips, and large rock on the bareflats. As a steam shovel must pick up what is nearest to it first, however, this classification could not always be adhered to, and manylarge rocks were loaded into dumpers. Cars of this class which containedno material too large to dump were run at once to the hoppers, and weredumped and returned to the pit; others, together with the flat and skipcars, were run down the incline to the derricks and telphers, where theflats and skips were entirely unloaded, and the large rocks ware removedfrom the dumpers, after which they were run to the hoppers and emptied. The total quantity of excavated material handled at this pier from May22d, 1905, to December 31st, 1908, amounted to 673, 800 cu. Yd. Of earthand 1, 488, 000 cu. Yd. Of rock, place measurement, equal to 3, 203, 400 cu. Yd. , scow measurement; in addition to which 175, 000 cu. Yd. Of crushedstone and sand and 6, 000 car loads of miscellaneous building materialwere transferred from scows and lighters to small cars for delivery tothe Terminal work. All the earth and 570, 000 cu. Yd. Of the rock, place measurement, werehandled through the chutes, and the remainder of the rock, 918, 000 cu. Yd. , and all the incoming material by the derricks and telphers. Incapacity to handle material, one telpher was about equal to one derrick. A train, therefore, could be emptied or a boat loaded under the bank ofeight telphers in one-fourth the time required by the derricks, of whichonly two could work on one boat. The telphers, therefore, were of greatadvantage where track room and scow berths were limited. As noted in the list of contracts under which the work was executed, the scows at both the 35th Street dumping board and Pier No. 72 werefurnished, towed, and the material finally disposed of, by Henry Steers, Incorporated. During the same period, this contractor disposed of thematerial excavated from both the Cross-town Tunnels, constructed by theUnited Engineering and Contracting Company, and the tunnels under theEast River, constructed by S. Pearson and Son, Incorporated. As statedin other papers of this series relating to the construction of thosetunnels, the material excavated by the United Engineering andContracting Company was delivered to barges at 35th Street and EastRiver and that by S. Pearson and Son, Incorporated, at two points, onein Long Island City and the other at 33d Street and East River, Manhattan. The total number of cubic yards of material disposed of amounted to: Place measurement. Total barge Earth. Rock. Measurement. 35th Street and North River 242, 800 22, 800 281, 500 Pier No. 72, North River 673, 800 1, 488, 000 3, 203, 400 From Cross-town Tunnels 570, 400 From Under-river Tunnels 402, 500 ----------- Total 4, 457, 800 =========== The material was delivered as follows: To the freight terminal of the Pennsylvania Railroad Company at Greenville, N. J. 3, 454, 800 To the Meadows Division of the Tunnel Line between Harrison, N. J. , and the North River Portals 711, 900 To other points selected by the contractors 291, 100 --------- Total 4, 457, 800 ========= The handling of this large quantity of material required the loading offrom 10 to 20 scows per day (and for more than two years the average was14), and, as the average time spent in one round trip was 3 1/3 days, afleet of more than 50 scows was required to keep all points supplied andallow for a few to be out of service undergoing repairs. All loaded scows were towed from the docks, with the ebb tide, to astake boat anchored in the bay about one mile off shore at Greenville;and were taken from there to the different unloading points, asrequired, by smaller tugs which also returned the empty scows to thestake. The unloading plants were similar at the different points, although thatat Greenville was much larger than the others. It included five landdredges and eight traveling derricks of two types, one floating and theother mounted on wheels and traveling on a track of 16-ft. Gauge. Thederricks handled the large rock, which was loaded at Pier No. 72 byderricks and telphers. They were of the ordinary A-frame type, and weredesigned to handle 20 tons. They were operated by 9 by 10-in. Lidgerwooddouble-drum and swinging-gear engines. The large rock was deposited bythe derricks either in the channels along which they worked or in thefill along shore, without the use of cars. The land dredges wereequipped with a 60-ft. Boom and a 2½-yd. Hayward bucket operated by a14 by 18-in. Double-drum Lidgerwood dredging engine. They loaded into9-yd. , standard-gauge, side-dump cars, built by the contractor, andunloaded the scows to within about 1 ft. Of the deck, a Hayward bucketbeing unsuitable for closer work without greatly damaging the scows. The material remaining was loaded by hand into skips which were handledto the cars by small derricks, one of which was located at the rear ofeach dredge. The cars were taken to the dump and returned by 25-ton, standard-gauge, engines which had previously done service on theManhattan Elevated Railroad, but were spotted for loading by the engineon the dredge. In order to keep a record of the fleet of scows, which would show theavailable supply at a glance, a board, 10 by 15 in. , and covered with aheavy sheet of ruled paper, was arranged as shown by Fig. 10. It wasdivided into 12 vertical columns, the first of which was headed "Scows, "and contained the name or number of each scow in service. The next fourcolumns denoted loading points, and were headed "Pier No. 72, ""Thirty-third Street, East River, " "Thirty-fifth Street, East River, "and "Long Island City, " respectively; the sixth column was headed"Greenville, " the seventh "Hackensack, " the eighth "Passaic, " and theninth "Governors Island, " being unloading points, the tenth andeleventh, "Stake Boat" and "Dry Dock, " respectively, while the twelfthwas for "Extra pins, " not in use. To indicate the condition of thescows, small pins with colored heads were used; white indicated empty;blue, working; black, loaded; red, being repaired; and a pearl-coloredpin, missing. Thus a white-headed pin opposite the number 6 in thecolumn headed Pier No. 72 indicated that scow No. 6 was lying at thatpier waiting to be placed in position for loading, whereas ablack-headed pin at the same point meant that the scow had receivedits load and was ready to be towed. BOARD RECORDING LOCATION AND CONDITION OF SCOWS [Transcriber's Note: This chart was originally presented as an illustration, Figure 10. It is shown here rotated from horizontal to vertical for readability. As in the original, only a partial board is shown; the number of Scows was at least 8. ] +---------------------+-------+-------+-------+-------+-------+-------/ | Scows. | H. S. | H. S. | H. S. | H. S. | H. S. | H. S. / | | No. 1 | No. 2 | No. 3 | No. 4 | No. 5 | No. 6 / +---------------------+-------+-------+-------+-------+-------+-------/ | Loading Points | | | | | | / +--+------------------+-------+-------+-------+-------+-------+-------/ | | Pier No. 72 | | | | | | / | +------------------+-------+-------+-------+-------+-------+-------/ | | Thirty-third | | | | | | / | | Street East R. | | | | | | / | +------------------+-------+-------+-------+-------+-------+-------/ | | Thirty-fifth | | | | | | / | | Street East R. | | | | | | / | +------------------+-------+-------+-------+-------+-------+-------/ | | Long Island City | | | | | | / +--+------------------+-------+-------+-------+-------+-------+-------/ | Unloading Points | | | | | | / +--+------------------+-------+-------+-------+-------+-------+-------/ | | Greenville. | | | | | | / | +------------------+-------+-------+-------+-------+-------+-------/ | | Hackensack. | | | | | | / | +------------------+-------+-------+-------+-------+-------+-------/ | | Passaic. | | | | | | / | +------------------+-------+-------+-------+-------+-------+-------/ | | Governors Island. | | | | | | / +--+------------------+-------+-------+-------+-------+-------+-------/ | Stake Boat. | | | | | | / +---------------------+-------+-------+-------+-------+-------+-------/ | Dry Dock. | | | | | | / +---------------------+-------+-------+-------+-------+-------+-------/ | | / | Extra Pins. | Empty. White Pins not in use placed here. / | | / +---------------------+-----------------------------------------------/ The scows were all taken from the general service about the harbor; someof them were practically new, while others had seen much service. Theywere of two general types, truss-framed or bulkhead-framed; all wereflat-bottomed, with a rake of about 45° at bow and stern. Thetruss-framed scows were built with a cross-truss every 10 to 15 ft. , onwhich rested, fore and aft, two classes of beams, main and intermediate. The main beams were built of timbers ranging from 10 by 10 in. To 14 by14 in. , were scarfed at the joints, and trussed with the bottom logs. The intermediate beams were of timbers varying from 6 by 6 in. To 10 by12 in. , had butt joints, and were dapped at the cross-trusses to give aconvex surface to the deck, which was built of 3-in. And 4-in. Plank, from 8 to 12 in. In width, running athwartship. The sides of the scowsof this class were spiked and bolted to trusses similar to those runningunder the main beams. The bulkheaded boats had both sides and twolongitudinal bulkheads placed so as to divide the scow into threesections of equal width, built of 8 by 8-in. Or 10 by 10-in. Timbers, laid one upon the other, and bolted through from top to bottom. Thebeams on these boats ran athwartship, rested on sides and bulkheads, andranged from 6 by 10-in. To 10 by 12-in. , spaced 2 ft. Apart, and dressedto give a convex surface to the deck, which was usually 3 in. , in somecases 4 in. , in thickness, and made up of narrow plank from 4 to 6 in. In width. [Illustration: Fig. 11. DIAGRAM OF DECK SHOWING BAYS] These boats had all been designed for lighter work than they were hererequired to perform, and a large amount of breakage occurred from thestart. In order that the contractors for the excavation should beunhampered as to method of loading, the contracts provided that theyshould pay for all damage done to the scows in loading, other thanordinary and usual wear and tear, all other damage being at the expenseof the contractor for the disposal. A rigid system of inspection wasnecessary to determine and record properly the damage for which eachcontractor was responsible; and, as much of the breakage could not benoticed from the exterior, a thorough examination of the interior ofeach scow was made before and after every loading. In order to keepproper records, the bays of each scow, formed by the cross-trusses, werenumbered, beginning aft with number 1 and going forward to the bow, andthe longitudinal bays formed by the main beams were lettered, beginningwith "_A_" on the port side. A beam broken in "1-_A_, " therefore, wouldbe an intermediate beam in the stern port corner bay, and a beam brokenin "10-_A-B_" would be a main beam at the bow end on the port side. Theunderside of each plank was marked with a number beginning with 1 at thestern and increasing by unity to the bow. Fig. 11 is a diagram of a scowin accordance with this system. In addition to recording the date, location, extent, and party responsible for each damage, in a book keptfor that purpose, the injured member was marked with paint, the color ofwhich indicated the party responsible. The repairs were made by thecontractor for the disposal of material, and the cost was assessedaccording to the marking in the boat. The careful inspection of the damage done to scows and the cost of theirrepairs enables a fairly accurate statement to be made of the amount atdifferent points, and it is here given on the basis of cost of repairsper cubic yard, barge measurement, of material handled. Cost, in cents per cubic yard. Repairs of damage done in loading material from the terminal site 2. 00 Repairs of damage done in loading material from cross-town tunnels 1. 32 Repairs of damage done in loading material from under-river tunnels 1. 77 Repairs of damage done in transporting and unloading material from all points 1. 81 The above figures do not include the expense due to scows which wereoverturned or sunk while in the service, which amounted to 0. 4 cent percubic yard, additional. _Ninth Avenue Tunnels. _--The two double-track tunnels under NinthAvenue, constructed to obtain 100 ft. Of additional tail room on eachof four tracks, required an excavation 76 ft. Wide, Fig. 12. The rock, although fair, was not firm enough for so great a span, and, to obviatethe necessity of timbering, the center wall was built before excavatingfor the full width. The dip of the rock at this point is almost 90°, andto prevent blowing away the entire face in excavating for the tunnel, the pit excavation was not carried west to the final face below thespringing line, a 10-ft. Bench being left at that elevation. A topheading 9 ft. High and 10 ft. Wide was started above that bench and, after penetrating about 10 ft. , was widened to 20 ft. A cross-headingwas driven in each direction at the west end of the first heading; thebench was then shot down, and the first 10 ft. Of the longitudinalheading was widened sufficiently to receive the center wall, Fig. 12. After the middle wall had been concreted, any voids between its topand the rock were grouted through pipes left for that purpose; the wallwas then protected by curtains of heavy round timber securely wiredtogether, and the remainder of the excavation was made by wideningthe cross-headings toward the face. The muck was carried out by twocableways, one on each side of the completed middle wall, each of whichwas supported by a tower outside of the tunnel and a large hook-boltgrouted into the rock at the inner end of the tunnel. Forms were builtfor each tunnel complete, and the concrete was delivered by a beltconveyor, running over the top of the lagging, and moved out as thetunnel was keyed. [Illustration: Fig. 12. TERMINAL STATION SKETCH SHOWING TWO TRACK TUNNELS AT NINTH AVENUE AND THIRTY-THIRD STREET] FOOTNOTES [1: Presented at the meeting of May 4th, 1910. ] [2: Reproduced as Plate IX in the paper by Mr. Noble. ] [Text reference for footnote 2: "one arm of the creek shown on General Viele's map of 1865" The article is ASCE 1152, The East River Division, available from