,,american ,,society ,,of ,,civil ,,engineers ,,instituted #aheb ,,transactions ,paper ,no4 #aaej ,,the ,,new ,,york ,,tunnel ,,extension ,,of ,,the ,,pennsylvania ,,railroad4 ,,by ,,charles ,w4 ,,raymond1 ,m4 ,,am4 ,,soc4 ,c4 ,e4,a ,some time before the appointment of the ,board of ,engineers which supervised the designing and construction of the ,new ,york ,tunnel ,extension of the ,pennsylvania ,railroad1 the late ,a4 ,j4 ,cassatt1 then ,president of the ,company1 said to the writer that for many years he had been unable to reconcile himself to the idea that a railroad system like the ,pennsylvania should be prevented from entering the most important and populous city in the country by a river less than one mile wide4 ,the result of this thought was the tunnel extension project now nearly completed2 but it is only in recent years that new conditions have rendered such a solution of the problem practicable as well as desirable4 ,previously a tunnel designed for steam railroad traffic1 to enter ,new ,york ,city near ,christopher ,street1 was partly constructed1 but the work was abandoned for financial reasons4 ,then plans for a great suspension bridge1 to enable all the railroads reaching the west shore of the ,north ,river to enter the city at the foot of #bc;d ,street1 were carefully worked out by the ,north ,river ,bridge ,company4 ,the ,pennsylvania ,railroad ,company gave this project its support by agreeing to pay its pro rata share for the use of the bridge2 but the other railroads declined to participate1 and the execution of this plan was not undertaken4 ,new operating conditions1 resulting from the application of electric traction to the movement of heavy railroad trains1 which had been used initially in tunnels by the ,baltimore and ,ohio ,railroad and was subsequently studied and adopted by railroads in ,europe1 made it possible to avoid the difficulty of ventilation connected with steam traction in tunnels1 and permitted the use of grades practically prohibitive with the steam locomotive4 ,the practicability of the tunnel extension project finally adopted was thus assured4 ,the acquisition of the control of the ,long ,island ,railroad by the ,pennsylvania ,railroad ,company1 which occurred in #aijj1 introduced new and important elements into the transportation problem1 from a freight as well as a passenger standpoint4 ,previously1 the plans considered had for their only object the establishment of a convenient terminus in ,new ,york1 to avoid the delays and difficulties involved in the necessity of transporting passengers and freight across the ,north ,river4 ,when the ,long ,island ,railroad became practically a part of the ,pennsylvania ,system1 it was possible and desirable to extend the project so as to provide1 not only for a great prospective local traffic from all parts of ,long ,island1 but also for through passenger and freight traffic to the ,new ,england ,states1 and to and from all points on the ,pennsylvania ,system1 thus avoiding the long ferriage from ,jersey ,city around the harbor to the ,harlem ,river4 ,this paper has for its subject the ,new ,york ,tunnel ,extension project1 and is intended merely as an introduction to the detailed accounts of the construction of the various divisions of the line to be given in succeeding papers prepared by the engineers who actively carried out the work4 ,the project1 however1 forms the most important part of the comprehensive scheme adopted by the ,pennsylvania ,railroad ,company for conducting its traffic into and through ,new ,york ,city1 and a brief description of this general plan is therefore necessary in order that the relations of the tunnel line to the other parts of the transportation project may be clearly understood4 ,,general ,,plan ,,for ,,traffic ,,facilities ,,at ,,new ,,york4 ,the component elements of the general plan outlined by the late ,a4 ,j4 ,cassatt1 ,president1 in his open letter to the ,board of ,rapid ,transit ,railroad ,commissioners of the ,city of ,new ,york1 dated ,january #ahth1 #aijf1 are indicated on ,fig4 #a1 and may be briefly summarized as follows3 #a4--,the ,pennsylvania ,tunnel and ,terminal ,railroad1 generally referred to as the ,new ,york ,tunnel ,extension of the ,pennsylvania ,railroad4 ,this line begins near ,newark1 ,n4 ,j41 crosses the ,hackensack ,meadows1 and passes through ,bergen ,hill and under the ,north ,river1 the ,borough of ,manhattan1 and the ,east ,river to the large terminal yard1 known as ,sunnyside ,yard1 in ,long ,island ,city1 ,borough of ,queens1 ,new ,york4 ,the line will be more fully described elsewhere4 #b4--,the electrification of the ,long ,island ,railroad within the city limits4 #c4--,the ,pennsylvania freight terminal yard and piers at ,greenville1 ,n4 ,j41 connecting by ferry with the ,bay ,ridge terminal of the ,long ,island ,railroad4 #d4--,the ,bay ,ridge ,improvement of the ,long ,island ,railroad from ,east ,new ,york to ,bay ,ridge4 #e4--,yards for increasing the freight facilities in the ,boroughs of ,brooklyn and ,queens4 #f4--,the ,atlantic ,avenue ,improvement in ,brooklyn1 involving the removal of the steam railroad surface tracks and the extensive improvement of the passenger and freight station at ,flatbush ,avenue4 #g4--,the ,new ,york ,connecting ,railroad1 extending through a part of the ,borough of ,queens and crossing the ,east ,river by a bridge at ,ward's and ,randall's ,islands to ,port ,morris1 ,n4 ,y4 #h4--,the ,glendale ,cut-,off of the ,long ,island ,railroad4 #i4--,new piers and docks in ,newtown ,creek at its confluence with the ,east ,river4 #aj4--;,electrification of the ,united ,railroads of ,new ,jersey ,division from ,newark to ,jersey ,city4 ,the parts sustained by these elements in the work of transportation and distribution are briefly as follows3 ,the ,new ,york ,tunnel ,extension is essentially a passenger line1 although the ,company has not only the legal powers but also the facilities for making it a through route for freight if desired4 ,it will transport passengers to and from the centrally located station at #cc;d ,street and ,seventh ,avenue in ,new ,york ,city1 joining the ,long ,island ,system at ,sunnyside ,yard1 and1 by means of the ,new ,york ,connecting ,railroad1 it will form a link in the through traffic line1 connecting the whole ,pennsylvania ,system with the ,new ,england ,states4 ,this line has been designed for the safe and expeditious handling of a large volume of traffic4 ,the requirements include handling the heaviest through express trains south and west from the main line as well as the frequent and lighter local-service trains4 ,for through service the locomotive principle of operation has been adhered to1 that is1 electric locomotives will take up the work of the steam locomotives at the interchange yard at ,harrison1 ,n4 ,j41 and1 for excursion and suburban service to nearby towns1 provision will be made for electric locomotives1 or by operation of special self-propelled motor cars in trains1 the project being planned to give the greatest flexibility in method of operation to meet the growing demand in the best way4 ,the ,new ,york ,connecting ,railroad has important functions both for freight and passenger service4 ,when constructed it will be about #ab miles long1 and will form a part of the line to the ,new ,england ,states for through passenger and freight service1 and also carry local freight to and from ,sunnyside ,yard and ,brooklyn1 and all points on ,long ,island4 ,by means of this line it will be possible to make the ,brooklyn station at ,flatbush ,avenue a station on the through ,system for ,new ,england as well as the ,western ,states4 ,illustration3 ,,fig4 #a4 7,full page image7 ,,map ,,of ,,the ,,pennsylvania ,r4 ,r4 ,,co',s ,,new ,,york ,,tunnel ,,extension ,,and ,,connections4 ,the initial equipment of the ,western ,division of the ,long ,island ,railroad for electric traction has been made in advance of the opening of the tunnel line in order to take care of the requirements of the ,atlantic ,avenue improvement4 ,this improvement involved the elimination of grade crossings within the ,city of ,brooklyn and the conversion of the railroad line which was previously on the surface of the streets to part subway and part elevated line from the ,flatbush ,avenue ,terminal to ,east ,new ,york ,station1 a distance of #e-a_/d miles4 ,one of the requirements of this improvement was that the motive power should be changed to some form of power not involving combustion4 ,this led to the adoption of electricity1 and1 in order to meet operating necessities1 involved the electrification of connecting lines beyond the improvement proper1 so that local service could be handled to the end of the runs without changing the motive power4 ,the extent of the electrification thus required was found to be about #ajj single-track miles4 ,this extensive electrification work was undertaken and completed in the summer of #aije1 upon the completion of the ,atlantic ,avenue improvement proper1 and since that time has been in successful operation4 ,on the near approach of the construction of the ,new ,york ,terminal improvement1 plans for additional electrification on the ,long ,island ,railroad were made1 and the work is now in progress on the extensive additions required to couple up the tunnel extension with the various lines centering at the ,long ,island ,city terminus4 ,the ,bay ,ridge ,improvement of the ,long ,island ,railroad comprises the readjustment of the right of way and the establishment of new grades in order to do away with grade crossings from the freight terminal at ,bay ,ridge to a junction with the ,new ,york ,connecting ,railroad at ,east ,new ,york1 a distance of #aj4d miles4 ,it also provides for the re-location of the line and the elimination of grade crossings on the branch running to ,manhattan ,beach1 a distance of #c4g miles4 ,the work is being executed without interrupting traffic1 and in all about #ge grade crossings will be abolished4 ,this improvement became necessary in order to provide for the rapid extension of population into the suburban districts and for the present and future requirements of the section1 to establish municipal conveniences and facilities1 and to open additional streets across the right of way4 ,to accomplish these ends1 the line has been built in cuts and on embankments1 there being about #f4d miles of the former1 #c4c miles of the latter1 and a tunnel1 #c1ejj ft4 long1 where the line crosses the ,atlantic ,avenue improvement4 ,the ,atlantic ,avenue improvement1 as mentioned above1 involved the removal of the railroad tracks from the street surface for a distance of about #e-a_/d miles4 ,this was done by constructing a series of elevated and subway structures1 there being about #b4a miles of the former1 #b4d miles of the latter1 and #j4h mile of approaches1 eliminating more than #ij grade crossings4 ,in the light of recent developments1 it may be of interest to note that one of the reasons for establishing a combination elevated and subway line was that1 at the time the improvement was projected1 no underground railroad in the country1 of similar length and carrying a heavy volume of local traffic1 was operated by electricity1 and public sentiment was against the operation of the entire length of the line underground by steam power4 ,this improvement also provided for depressing the entire ,flatbush ,avenue station and a freight yard4 ,as the work progressed1 the original plans for the station were greatly enlarged1 the remodeled station covering about #fa city lots4 ,the main point of passenger distribution is the ,new ,york station4 ,other important stations will be ,flatbush ,avenue1 ,brooklyn2 ,jamaica1 ,long ,island1 where the changes to and from electric motive power will be made2 and ,newark1 ,n4 ,j4 ,many other places1 including the seaside resorts on ,long ,island and in ,new ,jersey1 will feel the benefits of the direct tunnel railroad into and through ,new ,york ,city4 ,the ,glendale ,cut-,off will materially shorten the route and running time from ,new ,york through the tunnels to ,rockaway ,beach4 ,the plans contemplate that passengers to and from the lower part of ,manhattan will be carried by the steam line between ,newark and ,jersey ,city and cross the ,north ,river by ferry or the ,cortlandt ,street tunnels of the ,hudson ,company4 ,eventually1 the old main line will be electrified and supersede the steam service between ,newark and ,jersey ,city4 ,the ,greenville ,yard is the most important point for the receipt1 transmission1 and distribution of freight4 ,from this point freight can be transported1 without breaking bulk1 by a comparatively short car-ferry to the ,long ,island ,railroad terminus at ,bay ,ridge1 and thus a very large part of the ,pennsylvania ,railroad ,company's floatage in ,new ,york ,harbor and the ,east ,river will be abolished1 the floatage distance being reduced in the case of the ,new ,england freight from about #ab to #c miles4 ,this traffic will be routed from ,bay ,ridge via the ,long ,island ,railroad to a connection with and thence over the ,new ,york ,connecting ,railroad to the ,new ,york1 ,new ,haven and ,hartford ,railroad at ,port ,morris1 ,n4 ,y4 ,as the facilities for the handling of freight in the ,boroughs of ,brooklyn and ,queens had become insufficient for taking care of the prospective traffic1 eleven new local delivery yards1 having a combined area of about #b1aec city lots1 have been established1 and three existing yards are to be improved and enlarged so as to give a combined area of about #fhg city lots4 ,of these new yards1 the ,bay ,ridge freight terminal1 containing about #gij city lots1 is the largest2 its functions have been described above4 ,there is a freight terminal at ,east ,new ,york #bjj ft4 wide and a mile long1 containing about #eff city lots1 which will be the distributing point of freight for the entire ,east ,new ,york section4 ,this yard is depressed1 and will be crossed by six viaducts carrying city streets4 ,the ,north ,shore freight yard1 containing #aji city lots1 is connected with the ,montauk ,division by an overhead construction1 known as the ,montauk ,freight ,cut-,off1 whereby all freight traffic to ,jamaica may be kept out of the way of the ,jamaica passenger traffic from the tunnels4 ,it may be of interest to indicate briefly how much has already been accomplished in the execution of this general plan1 and what still remains to be done for its completion4 ,the larger part of the electrification of the ,long ,island ,railroad and the elimination of grade crossings within the built-up city limits1 the ,atlantic ,avenue improvement1 and the yard and piers at ,greenville1 have been completed4 ,the ,sunnyside ,yard and the ,glendale ,cut-,off will be completed during the next twelve months4 ,on the ,tunnel and ,terminal ,railroad the embankment and bridge work across the ,hackensack ,meadows and all the tunnels and excavation from the west side of ,bergen ,hill to ,long ,island ,city1 except a short section near the eastern end of the line1 have been completed4 ,the ,new ,york station and other buildings and facilities connected therewith are well advanced4 ,the laying of the track1 the electrification of the line1 and the installation of the signaling and lighting systems are under way4 ,it is anticipated that the line will be ready for operation in the spring of #aiaj4 ,report has been made to the ,public ,service ,commission that a large part of the right of way for the ,new ,york ,connecting ,railroad has been obtained1 and more than #c1jjj1jjj has been spent by this railroad4 ,the piers and docks at ,newtown ,creek and the electrification of the line from ,newark to ,jersey ,city are not yet actively under way4 ,,estimated ,,cost ,,of ,,the ,,improvements4 ,as appears from the foregoing statement1 only parts of the improvements contemplated in the general scheme have been completed1 others are in progress1 and others have not yet been commenced4 ,it is therefore impossible at the present time to make a close estimate of the total expenditure involved in the execution of the entire scheme4 ,the following estimate of the cost of the ,pennsylvania ,railroad ,company's improvements in the ,new ,york ,district when fully completed is based on the best information now available3 ,new ,york ,tunnel ,extension and ,station1 including ,interchange ,yards at ,harrison1 ,n4 ,j41 and ,sunnyside1 ,l4 ,i41 ,p4 ,t4 ,t4 ,r4 ,r4 ,co4 #ajj1jjj1jjj ,long ,island ,railroad electrification1 ,bay ,ridge and ,atlantic ,avenue improvements1 ,glendale ,cut-,off1 freight yards1 and new equipment #ce1jjj1jjj ,new ,york ,connecting ,railroad1 to be built jointly by the ,pennsylvania ,r4 ,r4 ,co4 and the ,new ,york1 ,new ,haven and ,hartford ,r4 ,r4 ,co41 about #ad1jjj1jjj ,pennsylvania ,railroad improvements in the ,state of ,new ,jersey1 electrification of line from ,jersey ,city to ,park ,place1 ,newark1 ,greenville freight line and terminal on ,new ,york ,bay #aj1jjj1jjj ------------ ,total #aei1jjj1jjj ,,corporate ,,organization ,,and ,,franchise ,,conditions4 ,as the tunnel extension lies partly in the ,state of ,new ,jersey and partly in the ,state of ,new ,york1 it was necessary to charter two companies1 each covering the territory within the ,state to which it belonged4 ,the ,new ,jersey corporation was entitled the ,pennsylvania1 ,new ,jersey and ,new ,york ,railroad ,company1 and the ,new ,york corporation1 the ,pennsylvania1 ,new ,york and ,long ,island ,railroad ,company4 ,these organizations were completed early in #aijb4 ,subsequently1 after the tunnels had been joined under the ,north ,river1 the companies were consolidated1 on ,june #bfth1 #aijg1 and thereby formed the present company under the name of the ,pennsylvania ,tunnel and ,terminal ,railroad ,company1 a corporation of both ,states4 ,mr4 ,cassatt1 ,president of the ,pennsylvania1 ,new ,york and ,long ,island ,railroad ,company1 made application in its behalf for a franchise to extend the lines of the ,pennsylvania ,railroad by tunnels under the ,north ,river to a passenger station to be erected in ,new ,york ,city and thence under the ,east ,river to a connection with the ,long ,island ,railroad1 on ,may #eth1 #aijb4 ,the franchise for that part of the tunnel line which is within the ,state of ,new ,york1 that is1 from the boundary line between ,new ,york and ,new ,jersey1 in the ,hudson ,river1 to the eastern terminus at ,sunnyside ,yard1 ,long ,island1 is contained in the certificate issued by the ,board of ,rapid ,transit ,railroad ,commissioners of the ,city of ,new ,york on ,october #ith1 #aijb4 ,the essential features of the franchise have been summarized substantially as follows in the report of the ,committee of the ,board of ,rapid ,transit ,railroad ,commissioners of the ,city of ,new ,york1 dated ,june #adth1 #aijb3 ,first4--,a grant by the city in perpetuity of rights1 subject1 however1 to a periodic readjustment of payments at intervals of twenty-five years1 as follows3 7a7 ,to construct and operate a railroad of two tracks from the boundary between ,new ,york and ,new ,jersey under the ,hudson ,river opposite the westerly foot of ,thirty-first ,street1 ,borough of ,manhattan1 thence running under the ,hudson ,river and ,thirty-first ,street to the ,east ,river and under the ,east ,river to a terminus in ,queens ,borough4 ,the ,company is permitted on notice within ten years to give up the right to these two tracks4 7b7 ,a like right for a railroad of two tracks beginning near the same point under the ,hudson ,river1 thence running under ,thirty-second ,street to the ,east ,river1 and under that river to the terminus in ,queens ,borough1 with a right for two additional tracks in ,thirty-second ,street1 west of ,ninth ,avenue1 and one additional track between ,seventh and ,fifth ,avenues in ,manhattan4 7c7 ,a like right for a railroad of two tracks beginning at the station terminal site at ,thirty-third ,street and ,seventh ,avenue and thence running under ,thirty-third ,street and the ,east ,river to the terminal in ,queens ,borough1 with a right for one additional track on ,thirty-third ,street1 between ,seventh and ,fifth ,avenues4 7d7 ,a right to maintain a terminal station occupying the four blocks bounded by ,thirty-first ,street1 ,seventh ,avenue1 ,thirty-third ,street and ,ninth ,avenue1 the lots on the east side of ,seventh ,avenue between ,thirty-first and ,thirty-third ,streets1 and the underground portions of ,thirty-first and ,thirty-third ,streets1 between ,seventh and ,eighth ,avenues and between ,eighth and ,ninth ,avenues1 the ,company having itself acquired the land included in such four blocks and lots on the east side of ,seventh ,avenue4 7e7 ,to occupy for such terminal facilities all of ,thirty-second ,street lying between the westerly side of ,seventh ,avenue and the easterly side of ,eighth ,avenue1 and between the westerly side of ,eighth ,avenue and the easterly side of ,ninth ,avenue4 ,as soon as the statutory right of the city authorities to make the conveyance shall be put beyond doubt the ,railroad ,company is obliged to buy such two portions of ,thirty-second ,street1 which will then become completely dedicated to the purposes of their station4 7,these portions of ,thirty-second ,street were subsequently purchased by the ,railroad ,company47 7f7 ,to have along such routes the necessary facilities for the operation of passenger and freight trains1 including telegraph wires and the various wires and cables for the distribution of power1 heat1 and light4 ,second4--,the requirement of the consent of the ,mayor1 the ,board of ,aldermen1 the ,board of ,estimate and ,apportionment1 and the other authorities of the city having control of the streets4 ,third4--,the obligation of the ,pennsylvania ,company to begin construction within three months after obtaining the necessary consents and complete the railroad within five years after construction shall begin1 except the route under ,thirty-first ,street1 for the completion of which the company is allowed ten years after the completion of the remainder of the railroad4 ,fourth4--,payments by the ,pennsylvania ,company for the first twenty-five years1 as follows3 ,a rental of #bjj per annum for the right to occupy land under the ,hudson and ,east ,rivers outside of pier lines4 ,a rental for ground within pier lines and for underground portions of streets in ,manhattan ,borough1 at fifty cents per linear foot of single track per annum1 for the first ten years1 and during the next fifteen years one dollar per annum per linear foot4 ,a rental for ground within pier lines and for underground portions of streets in ,queens ,borough at one-half the rates payable for ,manhattan ,borough4 ,a rental for underground portions of ,thirty-first and ,thirty-third ,streets1 between ,seventh and ,eighth ,avenues1 and between ,eighth and ,ninth ,avenues 7such portions extending almost up to the surface1 except under the south sidewalk of ,thirty-first ,street and north sidewalk of ,thirty-third ,street7 at #ad1jjj per annum for the first ten years1 and at #bh1jjj per annum for the next fifteen years4 ,for the portions of ,thirty-second ,street1 between ,seventh and ,eighth ,avenues1 and between ,eighth and ,ninth ,avenues1 when the statutory power of the city to make a sale shall be put beyond doubt1 the city is to sell and the ,railroad ,company is required to buy such portions for the sum of #ghh1fjj4 ,the rentals for river and track rights begin at the date of operation4 ,for the underground spaces under ,thirty-first and ,thirty-third ,streets1 used for station extension1 the rentals begin at the commencement of construction1 or when the company entered thereon4 ,such annual payments may be summarized as follows3 ,first #aj ,next #ae years4 years4 ---------------------------------------- ------------------------------- ,for river rights #bjj4jj #bjj4jj ,for tunnel rights in ,manhattan ,borough1 being #dd1cda ft4 7partly estimated7 of single track #bb1agj4jj #dd1cda4jj ,for tunnel rights in ,queens ,borough1 being #h1ajj ft4 7partly estimated7 of single track #b1jbe4jj #d1jej4jj ,for street rights on ,thirty-first and ,thirty-third ,streets1 north and south of terminal #ad1jjj4jj #bh1jjj4jj ---------------------------------------- ------------------------------- ,in all1 per annum #ch1cie4jj #gf1eia4jj ,if the route under ,thirty-first ,street be availed of1 these amounts will be increased by #af1feb4ej for the first ten years1 and by #cc1cje for the next fifteen years4 ,the amounts to be paid are to be readjusted at the end of twenty-five years2 and thereafter at intervals of twenty-five years4 ,if the city and the ,railroad ,company shall not agree upon the readjusted rates1 they are to be determined by the ,supreme ,court of this ,state4 ,fifth4--,the railroad to be entirely in tunnel except where it approaches the surface at its eastern terminal near ,thomson ,avenue1 in ,queens ,borough4 ,the uppermost part of the tunnel is to be at least nineteen feet below the surface of the street2 but this limitation does not apply to the portions of ,thirty-first and ,thirty-third ,streets opposite the terminal station between ,seventh and ,ninth ,avenues1 where the ,company may occupy the underground portions of the street under the roadway to within thirty inches of the surface1 and under the sidewalks on ,thirty-first and ,thirty-third ,streets opposite to the station to within five feet of the surface1 the company to properly care for sewers1 water1 gas and other pipes and underground structures lawfully in the street4 ,sixth4--,the company to make good all damage done to property of the city by its construction work or operations1 and to abutting owners all damage done through any fault or negligence of the company1 or of any contractor or sub-contractor engaged upon its work of construction or operation4 ,the ,tunnel ,company to keep ,thirty-first and ,thirty-third ,streets opposite the station well paved with smooth pavement and in thoroughly good condition4 ,seventh4--,tunnel excavations to be done without disturbing the surface of the street1 except in the portions of ,thirty-first and ,thirty-third ,streets1 and ,seventh1 ,eighth and ,ninth ,avenues in front of the terminal station1 and except in ,queens ,borough1 with the power to the ,rapid ,transit ,board1 wherever conditions elsewhere make surface excavation necessary for efficient construction1 to grant the right for such excavation1 subject to conditions to be then prescribed by the ,board4 ,the tracks are to be constructed of the most approved plan so as to avoid noise or tremor4 ,all plans for1 and the method of doing1 the work are made subject to the approval of the ,rapid ,transit ,board4 ,eighth4--,the motive power to be electricity1 or such other power not involving combustion as may be approved by the ,board4 ,ninth4--,the company to have no power to carry on merely local traffic1 except with the approval of the ,board and for additional consideration to be paid the city4 ,traffic is defined as local which begins and ends in the city within five miles of the terminal station on ,seventh and ,ninth ,avenues4 ,tenth4--,the railroad to be diligently and skillfully operated1 with due regard to the convenience of the traveling public4 ,eleventh4--,the city to have a lien upon the franchise and real property of the company to secure the payment of rental4 ,twelfth4--,the rights of the city to be enforceable by action1 for specific performance1 or mandamus1 or otherwise4 ,thirteenth4--,the company not to oppose the construction of any rapid transit railroad along or across the same routes which do not actually interfere with the authorized structures of the company4 ,fourteenth4--,the city to have an ample right of inspection of the railroad1 and to enter upon it for examination1 supervision1 or care of city property1 or for other purposes4 ,fifteenth4--,the company to be bound to maintain and strengthen all parts of its railways under streets or avenues so that the same shall support safely any structures superimposed or which may hereafter be superimposed thereon by the city or under public authority4 ,sixteenth4--,the company to have the right to convey or mortgage the franchise1 but every grantee1 whether directly or under a mortgage1 to assume the obligations already assumed by the ,railroad ,company and the ,railroad ,company not to be relieved of such obligations by the grant4 ,this franchise was passed by the ,board of ,aldermen on ,december #afth and approved by the ,mayor on ,december #bc;d1 #aijb4 ,subsequently1 an agreement1 dated ,june #bast1 #aijg1 was entered into by the ,city of ,new ,york1 the ,tunnel ,company1 and the ,long ,island ,railroad ,company covering the construction of the ,sunnyside ,yard1 which forms the eastern terminus of the line4 ,in pursuance of this agreement1 the map or plan of the ,city of ,new ,york was changed by discontinuing or closing portions of fifty streets or avenues1 and by changing the grades of sixteen streets or avenues1 in the ,borough of ,queens1 and the portions of streets and avenues thus discontinued and closed1 most of which were not opened for public use1 were sold to the ,railroad ,companies4 ,the agreement1 however1 reserved to the ,city permanent and perpetual underground rights and easements to maintain in a reasonable manner1 not inconsistent with the construction and operation of the railroad facilities of the ,companies1 its existing sewers1 drains1 and other sub-surface structures in1 under1 and through the lands within the lines of the discontinued portions of each of such streets and avenues1 including the right to repair1 rebuild1 and enlarge the same1 and to construct in a reasonable manner1 not inconsistent with the construction and operation of the railroad facilities of the ,companies1 such additional sewers or drains in1 under1 or through the lands as may be hereafter required by the ,city1 together with the right to enter upon the premises from time to time as may be necessary for the purpose of inspecting1 repairing1 constructing1 or rebuilding the sub-surface structures4 ,the agreement required the ,companies to construct at their expense1 four viaducts or bridges over their tracks and terminal development1 three with roadways #db ft4 wide1 one with a roadway #fj ft4 wide1 and each to have two sidewalks #aj ft4 wide1 the work to include the paving of the roadways and sidewalks4 ,the ,companies are further required to pay one-half the cost of the construction of the foundations1 abutments1 piers1 superstructures1 and approach of an additional viaduct or bridge over the ,sunnyside ,yard1 to have a roadway not more than #fj ft4 wide and two sidewalks each #aj ft4 wide1 and to grant the ,city of ,new ,york a perpetual easement for the continuance of the same in the location upon which it shall be constructed4 ,the agreement further provides that the ,companies shall not injure the sewers or other substructures now existing or hereafter constructed under the streets and avenues1 and1 in case of injury1 that they shall repair them or pay the cost thereof2 that the viaducts shall be completed within the shortest time consistent with their safe and proper construction1 and that during their construction temporary streets shall be provided for the accommodation of traffic4 ,the ,companies are required to bear all the expense of changes of grade in the streets and avenues1 except those made necessary by the construction of the viaduct or bridge to be paid for in part by the ,city2 to indemnify the ,city against all liability for any and all damages which may accrue on account of any street which may be closed or the grades of which may be changed in pursuance of the agreement2 to assume all liabilities by reason of the construction or operation of the railroads1 or the construction of the viaducts1 and to save the city harmless from any liability whatever1 to either persons or property1 by reason of the construction or operation of the railroads or the construction of the viaducts4 ,the ,companies are also required to indemnify the ,city against and pay the cost of all alterations which may be required to the sewerage or drainage system or to any sub-surface structures and pipes laid in the streets or avenues on account of the construction and operation of the terminal1 passenger yard1 or freight yard of the ,companies1 or on account of the changes in grades or street system4 ,the ,companies are authorized1 if they deem it necessary to the construction or to the efficient operation of the terminal passenger yard or freight yard1 to depress1 at their expense1 any pipes or other sub-surface structures now under the surface of any of the portions of the streets or avenues discontinued or closed1 or to elevate and carry the same upon any of the viaducts or bridges1 the plans of such depression or elevation to be approved by the ,board of ,estimate and ,apportionment4 ,all works within1 upon1 or over the public streets and avenues are subject to the supervision and inspection of the proper municipal officer or officers1 under such regulations as he or they may determine and be authorized by law to impose2 and the plans for the construction of viaducts or bridges are to be approved by the ,board of ,estimate and ,apportionment4 ,the ,companies are required to cede to the ,city of ,new ,york perpetual easements for the right to continue and maintain the viaducts or bridges over the streets and avenues1 sufficient for their control by the ,city for the purpose of police regulation and other control contemplated by the ,city ordinances for the case of streets or highways2 reserving1 however1 the right to construct and maintain1 at their own expense1 such connections between the viaducts or bridges and their property as shall not interfere with the use of the viaducts or bridges for street purposes4 ,the ,companies are also required to cede to the ,city1 grade and curb1 portions of five existing or proposed streets or avenues1 and to pave portions of two other avenues4 ,mr4 ,a4 ,j4 ,cassatt1 ,president of the ,pennsylvania ,railroad ,company1 was ,president of the ,companies constituting the ,new ,york ,tunnel ,extension until his death on ,december #bhth1 #aijf1 and ,mr4 ,james ,mc,crea1 ,president of the ,pennsylvania ,railroad ,company1 was elected his successor1 and is now ,president of the ,pennsylvania ,tunnel and ,terminal ,railroad ,company4 ,mr4 ,samuel ,rea1 ,second ,vice-,president of the ,pennsylvania ,railroad ,company1 has served as ,vice-,president since the incorporation of the enterprise4 ,mr4 ,a4 ,j4 ,county has been ,assistant to the ,president since ,june #bfth1 #aijg1 and prior thereto and from the incorporation of the tunnel enterprise served as ,secretary of the ,pennsylvania1 ,new ,jersey and ,new ,york ,railroad ,company and as ,assistant ,secretary of the ,pennsylvania1 ,new ,york and ,long ,island ,railroad ,company1 which1 as heretofore stated1 constitute the ,pennsylvania ,tunnel and ,terminal ,railroad ,company4 ,,engineering ,,organization4 ,mr4 ,rea1 ,vice-,president1 has general charge of all matters involved in the designing and execution of the project4 ,the ,board of ,engineers4--,before the beginning of the work1 the ,management appointed a ,board of ,engineers which was instructed to examine into the ,new ,york ,tunnel ,extension project2 to pass upon the practicability of the undertaking2 to determine upon the best plans for carrying it out2 to make a careful estimate of its cost2 and1 if the work was undertaken1 to exercise general supervision over its construction4 ,president ,cassatt's letter appointing the ,board contains the following further instructions3 ,you are requested to procure all additional information that may be needed1 sparing neither time nor any necessary expense in doing so1 for ,i am sure it is not necessary for me to say that1 in view of the magnitude and great cost of the proposed construction1 and of the novel engineering questions involved1 your studies should be thorough and exhaustive1 and should be based upon absolute knowledge of the conditions4 ,the ,board was organized on ,january #aath1 #aijb1 when it held its first session1 and continued in the performance of its duties until ,april #cjth1 #aiji1 when it was dissolved1 its work having been completed4 ,the ,board held regular and special sessions to receive progress reports from the ,chief ,engineers in direct charge of construction1 and to consider questions relating to the plans and details of the work submitted by its members or referred to it by the ,management4 ,it then reported its conclusions to the ,vice-,president for approval before the work was undertaken4 ,the ,management earnestly impressed upon the ,board throughout the whole period of its labors1 that the ,tunnel ,extension and facilities were to be designed and constructed without regarding cost as a governing factor1 the main considerations being safety1 durability1 and proper accommodation of the traffic4 ,no expenditure tending to insure these conditions was to be avoided4 ,the ,board1 when organized1 was composed as follows3 ,col4 ,charles ,w4 ,raymond1 ,corps of ,engineers1 ,u4 ,s4 ,army1 ,chairman2 ,messrs4 ,gustav ,lindenthal1 ,charles ,m4 ,jacobs1 ,alfred ,noble1 and ,william ,h4 ,brown4 ,mr4 ,george ,gibbs was appointed a member of the ,board on ,april #ith1 #aijb4 ,mr4 ,lindenthal resigned on ,december #aeth1 #aijc1 and ,mr4 ,brown resigned on ,march #ast1 #aijf4 ,mr4 ,rea and all the members of the ,board are members of the ,american ,society of ,civil ,engineers1 and ,mr4 ,noble is a ,past-,president of the ,society4 ,mr4 ,william ,r4 ,mead1 of the firm of ,mc,kim1 ,mead1 and ,white1 ,architects for the ,terminal ,station1 was associated with the ,board for the consideration of architectural subjects4 ,mr4 ,robert ,h4 ,groff1 ,secretary of the ,company1 was also ,secretary of the ,board until his resignation on ,january #cast1 #aijg4 ,mr4 ,william ,couper was ,acting-,secretary from ,april #aeth1 #aijg1 to ,april #cjth1 #aiji4 ,s4 ,johannesson1 ,assoc4 ,m4 ,am4 ,soc4 ,c4 ,e41 was ,engineer ,assistant to the ,chairman from ,december #ast1 #aije1 to ,april #cjth1 #aiji4 ,division of the ,work4--,for the purposes of actual construction1 the line was divided into four parts3 the ,meadows ,division1 the ,north ,river ,division1 the ,terminal ,station1 and the ,east ,river ,division4 ,a chief engineer appointed by the ,management had charge of the construction of each ,division4 ,the chief engineers exercised full authority in the organization of the working forces1 and in the general conduct and management of the work of construction on their respective ,divisions1 in accordance with the plans for such work approved by the ,board of ,engineers and the ,management4 ,architects were employed to design the ,terminal ,station building and superintend its erection2 and structural engineers to design and erect steel structures and facilities1 and carry on the work under the direction of a ,chief ,engineer of the ,company4 ,committees1 consisting principally of officers of the ,pennsylvania ,railroad ,company1 co-operating with the regular engineering organization1 were appointed to consider the operating features of the project1 so that the experience of the ,pennsylvania ,railroad ,company's organization might be utilized in the work4 ,illustration3 ,,plate ,i4--,pennsylvania ,tunnel and ,terminal ,railroad4 ,map and ,profile4 ,bergen ,hill ,tunnel1 ,new ,jersey to ,long ,island ,shaft1 ,borough of ,queens ,,description ,,of ,,the ,,line4 ,the following summary description of the various divisions of the line is intended to give a comprehensive idea of the general features of the project4 ,full details will be given in succeeding papers4 ,the line and its respective divisions are shown on ,plate ,i4 ,meadows ,division4--,chief ,engineer until ,march #ast1 #aijf1 ,mr4 ,william ,h4 ,brown1 ,chief ,engineer1 ,pennsylvania ,railroad ,company1 when he retired from active service with the latter ,company2 since ,march #ast1 #aijf1 ,mr4 ,alexander ,c4 ,shand1 ,chief ,engineer1 ,pennsylvania ,railroad ,company4 ,this ,division consists of an interchange yard at ,harrison1 near ,newark1 ,n4 ,j41 adjoining the tracks of the present ,new ,york ,division of the ,pennsylvania ,railroad1 and a double-track railroad across the ,hackensack ,meadows to the west side of ,bergen ,hill1 a distance of #f4jd miles4 ,the construction is embankment and bridge work1 including bridges across the ,pennsylvania1 ,erie1 and ,lackawanna ,railroads1 and the ,hackensack ,river4 ,north ,river ,division4--,chief ,engineer1 ,mr4 ,charles ,m4 ,jacobs4 ,this ,division commences at the west side of ,bergen ,hill and passes through the hill in two single-track rock tunnels to a large permanent shaft at ,weehawken1 near the west shore of the ,north ,river1 and thence eastward a distance of #bbd ft4 to the ,weehawken shield-chamber4 ,it then passes under the river through two cast-iron1 concrete-lined1 single-track tunnels1 with outside diameters of #bc ft41 to a point under #cb;d ,street1 near ,eleventh ,avenue1 in ,new ,york ,city1 and thence through two single-track tunnels of varying cross-section1 partly constructed in cut-and-cover1 to the east side of ,tenth ,avenue4 ,it then passes into the ,station ,yard and terminates at the east building line of ,ninth ,avenue4 ,the work included the ,station ,yard excavation and walls from ,tenth ,avenue to ,ninth ,avenue1 and the retaining walls and temporary underpinning of ,ninth ,avenue4 ,the aggregate length of the line in this ,division is #b4gf miles4 ,new ,york ,station and ,approaches4--,mr4 ,george ,gibbs1 ,chief ,engineer of ,electric ,traction and ,station ,construction4 ,the ,station and its approaches extend from the east line of ,tenth ,avenue eastward to points in #cb;d ,street and #cc;d ,street1 respectively1 #bib ft4 and #ejb ft4 east of the west line of ,seventh ,avenue4 ,this ,division included the construction of subways and bridges for the support of #cast and #cc;d ,streets and ,seventh1 ,eighth1 and ,ninth ,avenues1 the ,station building between ,seventh and ,eighth ,avenues1 the foundations for the post office to be erected west of ,eighth ,avenue1 the service power-house in #cast ,street between ,seventh and ,eighth ,avenues1 the power-house in ,long ,island ,city1 the traction system1 tracks1 signals1 and miscellaneous facilities required in the physical construction of the entire terminal railroad ready for operation4 ,messrs4 ,mc,kim1 ,mead1 and ,white were the architects for the ,station and ,messrs4 ,westinghouse1 ,church1 ,kerr and ,company executed the structural engineering work1 both in the station and for the support of the streets1 as well as the construction of the subways4 ,the station is of steel skeleton construction with masonry curtain walls1 all supported by a system of columns extending to a rock foundation4 ,this building covers two city blocks and one intersecting street1 and has an area of about #h acres4 ,it is #ggd ft4 long1 #dcc ft4 wide1 with an average height above the street of #fi ft41 and a maximum of #aec ft4 ,the main waiting-room is #bgg ft4 long1 #ajc ft4 wide and #aej ft4 high4 ,the ,concourse is #cdj ft4 long and #baj ft4 wide4 ,the level of the track system below the street surface varies from #ci to #eh ft41 and is from #g to #aj ft4 below mean high water in the harbor1 thereby necessitating the establishment of an elaborate system of drainage over the entire station yard area4 ,access to the street is gained by elevators and stairways4 ,to accelerate the loading and unloading of the trains1 high platforms will be constructed in the station on a level with the floors of the cars1 in order to avoid the use of car steps and increase the traffic capacity of the station4 ,there will be #ba standing-tracks at the station1 and #aa passenger platforms1 providing #ba1ejj ft4 of platform adjacent to passenger trains4 ,within the station area1 which from ,tenth ,avenue to the normal tunnel sections east of ,seventh ,avenue comprises #bh acres1 there will be a total of about #af miles of track4 ,the service plant for the installation of machinery for lighting1 heating1 and ventilating the station1 and for operating the interlocking system1 is located in an independent building south of the station4 ,the ,power-,house to supply the electrical energy for the operation of the tunnel line and the ,long ,island ,railroad is situated on property in ,queens ,borough adjoining the present ,long ,island ,railroad ,station near the ,east ,river1 and was constructed under the ,chief ,engineer of ,electric ,traction and ,station ,construction4 ,as at present designed1 the dimensions of the structure are #bjj ft4 by #bfb ft41 outside measurement4 ,it can accommodate six generating units of #e1ejj kw41 the standard adopted for future work1 and two of #b1ejj kw4 for lighting the tunnels4 ,the ultimate capacity of this station when extended will be about #aje1jjj kw4 ,east ,river ,division4--,chief ,engineer1 ,mr4 ,alfred ,noble4 ,this ,division begins at the eastern limits of the ,new ,york ,station at a point in #cb;d ,street1 #bib ft4 east of the west line of ,seventh ,avenue1 and at a point in #cc;d ,street1 #ejb ft4 east of the west line of ,seventh ,avenue1 and also includes the excavation work and retaining walls for the station site and yard1 to the track level1 westward to ,ninth ,avenue4 ,it extends eastward from the station under #cb;d and #cc;d ,streets through tunnels partly three-track and partly so-called twin tunnels to ,second ,avenue2 thence the line curves to the left under private property to permanent shafts a few feet east of ,first ,avenue4 ,four single-track1 cast-iron1 concrete-lined tunnels1 with outside diameters of #bc ft41 pass under the ,east ,river1 and1 after passing through permanent shafts near the bulkhead line1 reach the surface in ,long ,island ,city from #c1jjj to #d1bjj ft4 east of the ,east ,river4 ,the tunnel portals are in ,sunnyside ,yard1 which extends to ,woodside1 the easterly end of the ,division1 and the ,yard grading with its buildings and a number of ,city viaducts crossing it were executed under this ,division4 ,the total length of the ,division is #d4dh miles4 ,the total length of the entire line is #ac4ff miles4 ,there are #f4gh miles of single-track tube tunnels1 and the average length of the tunnels between portals is #e4ef miles4 ,illustration3 ,,plate ,,ii4--,pennsylvania ,tunnel and ,terminal ,railroad4 ,map and ,profile4 ,harrison ,yard to ,bergen ,hill ,tunnel4 ,meadow ,division ,july #cj #aiji ,,general ,,considerations4 ,details have been omitted from the foregoing description1 as they can be treated better and more fully by the constructing engineers in succeeding papers4 ,there are1 however1 some general considerations involved in the designing of the work1 which may1 perhaps1 be referred to more conveniently in this introductory paper1 and these will now receive attention4 ,in all parts of the work problems were encountered requiring for their solution large expenditures and much engineering skill2 but many of these difficulties had been frequently met in previous engineering experience1 and the methods of overcoming them were well understood4 ,thus1 in the ,meadows ,division1 a long and heavy embankment1 part of which was on submerged meadow land1 and many bridge foundations had to be constructed2 in the ,bergen ,hill tunnels1 very tough trap rock was encountered2 in the tunnels under the city1 the work was much complicated and its cost increased greatly by the necessity of caring for sewers1 water and gas pipes1 and the foundations of adjacent buildings2 and many troublesome problems were met in the construction of the tunnels connecting the ,east ,river tunnels with the ,sunnyside ,yard4 ,the novel features of the project1 however1 were the great tunnels extending the line under the ,north and ,east ,rivers4 ,tunnels of the kind contemplated1 to be used for heavy and rapid railroad traffic1 had never been constructed through materials similar to those forming the beds of the ,north and ,east ,rivers4 ,questions arising in connection with the design and method of construction of the tunnels will be considered later4 ,here they are referred to only in their relation to the location and grades of the line1 in which connection the conditions controlling their establishment were the most important elements4 ,location and ,grades4--,it was desirable to make the tunnels between the bulkhead lines of the rivers as straight as possible1 and it was necessary to place them at sufficient depth below the dredging plane of the ,war ,department 7which in the ,north and ,east ,rivers is #dj and #bf ft4 below mean low water1 respectively7 to insure them against possible injury from heavy anchors or sunken vessels4 ,furthermore1 they had to pass under the piers and bulkheads of ,manhattan at a depth sufficient to make it certain that they would not affect the stability of those structures4 ,another consideration influencing the establishment of the depth of the tunnels below the bottoms of the rivers became important as soon as the method of construction by shields with compressed air was adopted1 namely1 the necessity of providing sufficient cover to guard1 as far as possible1 against blow-outs during construction4 ,the tunnels under the city1 connecting the sub-river tunnels with the ,terminal ,station1 were located so as to give as favorable grades as possible4 ,the provision of the franchise requiring the tops of the tunnels to be at least #ai ft4 below the ,street surface1 which had been suggested by the ,company to permit of future subways1 had no effect on their location1 as other conditions required them to be at a greater depth4 ,the line extending westward from ,bergen ,hill had to be established so as to give ample head-room at the numerous bridges over the railroads and highways which it crosses4 ,eastward from the ,east ,river tunnels1 the grades were established so as to rise as uniformly as possible to the level of the ,sunnyside ,yard4 ,the general features of the line1 as finally adopted and constructed1 are as follows3 ,the maximum grade west of the ,terminal ,station occurs on the ,new ,york side of the ,north ,river1 and is #b in the west-bound and #a4ic in the east-bound tunnels4 ,the ruling grades 7for the ascending traffic7 being #a4cb in the west-bound and #a4ic in the east-bound tunnels4 ,in the tunnels east of the ,terminal ,station the ruling grade is #a4e for both east-bound and west-bound traffic4 ,there is1 however1 descending with the traffic1 a short section on a grade of #a4i per cent4 ,these grades would be objectionable with steam locomotives under a heavy traffic1 but the development of the electric locomotive has rendered possible the operation of grades which would have formerly been considered prohibitive4 ,from the junction with the ,pennsylvania ,railroad1 near ,harrison1 ,n4 ,j41 to ,woodside1 ,long ,island1 a distance of #ac4ff miles1 there is an average of #a4e curves per mile2 the line having a total curvature of #bcj degrees4 ,the maximum curvature is #b degrees4 ,illustration3 ,,plate ,,iii4--,p4 ,t4 ,t4 ,r4 ,r4 ,east ,river ,division4 ,sunnyside ,yard ,method of ,construction of ,sub-,river ,tunnels4--,the character of the material through which the tunnels were to be constructed differed greatly in the two rivers4 ,the bed of the ,north ,river1 at the level of the tunnels1 consists of silt composed principally of clay1 sand1 and water1 while that of the ,east ,river is formed of a great variety of materials1 such as quicksand1 sand1 boulders1 gravel1 clay1 and bed-rock4 ,when the method of construction had to be decided there were no thoroughly satisfactory precedents to follow in the case of either river1 although the ,gas ,tunnel under the ,east ,river1 the partly constructed ,hudson ,tunnels under the ,north ,river1 the ,st4 ,clair ,tunnel under the ,st4 ,clair ,river1 the ,blackwall and several other tunnels under the ,thames ,river at ,london1 supplied much useful information4 ,the smaller tunnels for a lighter traffic1 since so successfully constructed under the ,north and ,east ,rivers1 had not then been completed4 ,under these circumstances1 it was the desire of the ,management that the ,board should receive and consider proposed methods of construction from all available sources2 and during the first year of its labors much of its time was devoted to the examination and discussion of projects submitted for its consideration by engineers and practical builders1 some of these projects having decided merit4 ,most of the methods proposed involved temporary structures1 or the use of floating plant1 in the navigable channels of the river4 ,this was objectionable in view of the resulting obstruction to the enormous river traffic4 ,after full consideration of the subject1 it was decided to adopt the shield method with compressed air for the construction of the tunnels under both rivers1 this being the only method recommended by the ,chief ,engineers1 and having the great advantage of conducting all operations below the bottom of the river1 thus avoiding obstruction of the channel4 ,experience has shown1 as was anticipated1 that it is much more difficult to construct tunnels in such material as occurs in the ,east ,river and on the ,new ,jersey side of the ,north ,river1 than in more homogeneous material such as is found in the greater part of the ,north ,river4 ,during the progress of construction under the ,east ,river1 there were frequent blow-outs through fissures opened in the river-bed1 and the bottom of the river over the tunnel had to be blanketed continuously with clay1 to check the flow of the escaping air4 ,in view of the serious difficulties which it was thought might be encountered in the application of the shield method to the ,east ,river work1 other methods for the execution of this part of the project received special consideration1 one of the methods considered being the freezing process4 ,it was proposed to drive a small pilot tunnel and freeze the ground for a sufficient distance around it by circulating brine through a system of pipes established in the tunnel4 ,the pilot tunnel was then to be removed and the full-sized tunnel was to be excavated in the frozen material and its lining placed in position4 ,by this means1 it was intended to avoid the danger incident to the use of compressed air in material of greatly varying character4 ,this method contained too many elements of uncertainty to justify its adoption2 but as the ,management considered it desirable to have1 if possible1 an alternative method1 an extended experiment was made with the freezing process4 ,a pilot tunnel1 #g ft4 #f in4 in diameter1 was driven in the bed of the ,east ,river for a distance of #afj ft41 circulating pipes were established in it1 and brine at a very low temperature was passed through the pipes until the ground was frozen for a distance of about #aa4e ft4 around the tunnel4 ,observations to determine the rate of cooling and other important points connected with the process were carefully made4 ,when it was found that the construction of the tunnels was progressing satisfactorily by the shield method1 and that so much time was required to freeze the material that the freezing process could not be used to advantage in this particular case1 the experiment was discontinued4 ,design of the ,sub-,river ,tunnels4--,the sub-river tunnels consist of a circular cast-iron shell1 of the segmental1 bolted type1 having an outside diameter of #bc ft41 lined with concrete having a normal thickness of #b ft4 from the outside of the shell4 ,through each plate of the shell there is a small hole1 closed with a screw plug1 through which grout may be forced into the surrounding material4 ,each tunnel contains a single track4 ,a concrete bench1 the upper surface of which is #a ft4 below the axis of the tunnel1 is placed on each side of the track1 the distance between benches being #aa ft4 #h in4 ,these benches contain ducts for carrying electric cables4 ,the main reason for adopting single-track tunnels instead of a larger tunnel containing two tracks was to avoid the danger of accidents due to the obstruction of both tracks by derailment or otherwise4 ,the tunnels are made just large enough to allow the passage of a train with perfect safety1 as it was believed that with such an arrangement thorough ventilation would be secured by the motion of the trains4 ,experience seems to justify this assumption1 but1 in order to assure thorough ventilation under unusual conditions1 such as the stoppage of trains in the tunnels1 a complete ventilating plant will be provided for each tunnel4 ,the rapidity and safety of construction were increased by making the tunnel as small as possible1 one of the difficulties in the shield method of construction being the difference in hydrostatic pressure between the top and bottom of the shield1 which increases with the diameter of the tunnel4 ,the concrete lining was introduced to insure the permanency of the structure1 strengthen it from outward pressure and guard it against injury from accidents which might occur in the tunnel4 ,the side concrete benches were suggested by ,mr4 ,cassatt1 ,president1 to confine the trains to the center of the tunnels in case of derailment1 and to furnish sidewalks on each side of the trains so as to obviate the necessity of walking on the track4 ,refuge niches are constructed in the side benches of the tunnels4 ,manholes1 splicing chambers1 pump chambers1 and other features for the handling of the electric cables and drainage1 are established at intervals4 ,at points where unusual stresses were anticipated1 as for instance where the tunnels pass from rock to soft ground1 the shell was composed of steel instead of cast-iron plates4 ,in the ,north ,river tunnels the concrete lining in the invert and in the arch was reinforced by longitudinal steel bars1 but these were not introduced in the ,east ,river tunnels4 ,other details connected with the structures1 including the drainage1 lighting1 ventilation1 signaling1 and electrification systems1 will be given in succeeding papers4 ,stability of the ,sub-,river ,tunnels4--,one of the most important questions connected with the design of these tunnels was their probable stability under the long-continued action of a heavy and rapid railroad traffic4 ,the tunnels are lighter than the materials which they displace even when the weight of the heavy live load is included4 ,in the ,east ,river the character of the material seemed to justify the conclusion that the tunnels would not be displaced even under the action of the live load4 ,in the ,north ,river1 however1 the tunnels are enveloped by a soft silt and it was at first apprehended that some system of supports would be advisable to carry the heavy traffic and insure the tunnels against displacement under its action4 ,to meet this contingency1 which was then believed to be a very serious one1 it was proposed to sink cast-iron screw-piles through the bottom of each tunnel into and through the underlying silt until satisfactory bearing material was reached4 ,the pile supports were worked out in sufficient detail to be embraced in the contract for the construction of these tunnels1 with provision1 however1 for omitting them should it be determined subsequently that their use was undesirable4 ,the contract plans contained provisions for sliding joints where the piles pass through the tunnel floor1 so that the live load might be carried directly to the pile heads by a system of girders1 and also for attaching the piles directly to the tunnel1 the two plans being alternatives4 ,investigations1 made during the progress of the work to determine the physical character of the silt and its action on the tunnels1 suggested the possibility that the use of pile supports might be inadvisable4 ,this view was confirmed by actual experience in the operation of the tunnels of the ,hudson ,companies between ,hoboken1 ,n4 ,j41 and ,morton ,street1 ,manhattan1 which were opened to traffic in ,february1 #aijh4 ,the stability of these tunnels under traffic gave further assurance that supports were unnecessary under the ,north ,river tunnels of the ,pennsylvania ,railroad ,company1 and they were therefore dispensed with4 ,cross-,passages ,between the ,tunnels4--,the ,bergen ,hill tunnels1 the land portions of the ,north ,river tunnels and the tunnels under ,manhattan are connected by cross-passages at intervals varying from #ej to #cjj ft4 ,as it was the desire of the ,management to provide every arrangement possible to insure the safety of its passengers and employees and also to provide for the convenience of inspection1 the question of establishing cross-passages between the tunnels under the rivers was given most careful consideration4 ,the conclusion was finally reached that such passages as it was possible to construct between these tunnels might increase instead of diminish the danger in case of accident4 ,no more cross-passages have therefore been constructed in the sub-river sections1 except in the ,east ,river1 where there is a cross-passage and pump chamber combined between each pair of tunnels about #gej ft4 from the ,manhattan bulkhead line4 ,,probable ,,results ,,of ,,the ,,improvements4 ,in preceding pages reference has been made to the general objects of the improvements included in the project of the ,pennsylvania ,railroad ,company for the ,new ,york ,district4 ,while it is impossible1 in this introductory paper1 to analyze fully the transportation problem at ,new ,york1 it seems desirable to indicate briefly some of the more obvious effects which the improvements may be expected to produce upon the distribution and handling of traffic4 ,new ,york ,city owes its position as the business metropolis of the country mainly to its magnificent harbor and the extensive waterfronts on its deep1 wide rivers1 which furnish unrivaled facilities1 at a short distance from the sea1 for foreign and domestic water-borne commerce1 its foreign commerce being about half the total for the whole country4 ,the water-transportation facilities of the port and its tributaries1 therefore1 have always been guarded with jealous care1 not only by the local commercial interests but also by the ,general ,government4 ,during recent years1 however1 the population of the metropolitan district has increased so enormously that ,new ,york is now the greatest terminal passenger and freight traffic center in the country2 and in manufactures it ranks first among ,american cities4 ,the new commercial interests thus created are of at least equal importance with those of the water-borne commerce1 although their existence and development are largely the result of the water facilities of the port4 ,the local passenger and freight traffic of the ,pennsylvania and of other railroads reaching the west shore of the ,north ,river is conducted by car-floats and ferry-boats which deliver their loads at piers on the ,manhattan waterfront and elsewhere in the harbor4 ,these boats obstruct and endanger the free navigation of the channels and occupy space along the waterfront greatly needed for the accommodation of the long-distance water-borne commerce1 especially on the ,north ,river4 ,in the ,east ,river the importance of ferry-boats as a means of traffic distribution has already been greatly reduced by the construction of bridges and tunnels which provide for the greater part of the passenger and vehicular traffic4 ,the ,north ,river1 however1 by reason of its greater width and the comparative slowness of its currents1 is by far the more important waterway for the use of ocean-going vessels of the larger classes4 ,in this river the conditions for the construction of bridges1 within the limits of commercial convenience1 seem to be practically prohibitory4 ,tunnels1 for the transportation of passengers and the diversion of the freight traffic from the inner waters of the harbor1 are apparently the only available means of relief4 ,when the new line is in operation1 a very large part of the ,new ,york passenger traffic of the ,pennsylvania ,railroad will be carried to the ,new ,york ,station at ,seventh ,avenue and #cc;d ,street and the rest will go to ,cortlandt ,street through the ,hudson ,company's tunnels4 ,thus a large portion of the ,pennsylvania passenger ferry traffic1 which amounts to more than #ia1jjj passengers daily1 will be practically eliminated from the water-transportation problem4 ,in addition1 a large part of the ,long ,island ,railroad's passengers will use the station at ,seventh ,avenue and #cc;d ,street1 and its ferry traffic will be reduced accordingly4 ,the new arrangements for the transfer of freight from ,greenville to ,bay ,ridge will relieve the inner waters of the harbor of a large volume of obstructive car-float traffic4 ,there appears to be no reason why this traffic should not be eventually conducted through tunnels under the outer harbor1 should future transportation conditions justify the enormous cost of such structures4 ,it is to be remarked that while these new arrangements greatly reduce the passenger and freight water transportation1 they have no effect on the large vehicular traffic across the ,north ,river which must continue to be conducted by ferries until it can be otherwise provided for4 ,as long as these conditions exist1 ferry-boats must be used in large numbers and continue to obstruct the ,north ,river4 ,this difficulty probably cannot be overcome by the construction of bridges1 as in the case of the ,east ,river1 but it does not seem too much to expect that1 eventually1 tunnels to provide for the vehicular traffic1 like the ,blackwall tunnel under the ,thames1 will be established under the ,north ,river4 ,it would be interesting to estimate the increase in railroad traffic capacity resulting from these improvements1 but the data required for this purpose are not available4 ,some idea of the increase in passenger traffic capacity resulting from the establishment of the tunnel line may be obtained by comparing the proposed daily train-movements for the new station with the train-movements at other important railroad stations4 ,the daily train-movements of six such stations are given in the following table3 ,total trains ,movement in and out at for #bd hours4 maximum hour4 ,jersey ,city #bha #bi ,broad ,street ,station1 ,philadelphia #ech #dh ,union ,station1 ,st4 ,louis #dfb #hi ,south ,terminal ,station1 ,boston #hfa #hg ,grand ,central ,station1 ,new ,york #ceg #dd ,pennsylvania ,station1 ,new ,york,b #ejj #ej ,,footnotes3 ,footnote ,b3 ,proposed train service when ,station is opened1 the ultimate capacity of the ,station being in excess of #a1jjj trains per day4 ,the freight capacity of the ,pennsylvania ,system at ,new ,york has been greatly enlarged by the construction of the ,greenville ,yard and the facilities connected therewith1 but it is impossible to estimate the amount of this increase4 ,however1 it is worthy of remark that1 during the period from #aijj to #aijf1 the freight traffic density on the directly-operated lines of the ,pennsylvania ,railroad ,company increased from #c1bfh1ccj to #d1gdb1jha ton-miles per mile of road1 a growth of nearly #ej per cent4 ,doubtless the improved freight facilities of the ,new ,york ,district had a large influence in the development of this increase4 ,one of the most interesting points connected with this development of traffic facilities is its influence on the relative distribution of population in the different parts of the metropolitan district4 ,in #aijg the population per acre of the different divisions of ,greater ,new ,york was reported as follows3 ,manhattan1 #aeg2 ,brooklyn1 #bi2 ,bronx1 #ad2 ,queens1 #c2 ,richmond1 #b4 ,the effect of new lines connecting some of these districts1 and sections of ,new ,jersey not far from the ,north ,river1 with the business center of the city will undoubtedly be to increase greatly their population-density4 ,it does not seem probable that the population-density of ,manhattan will be sensibly reduced by these improvements1 for they stimulate the increase of population1 and apparently no increase of transportation facilities can keep up with the growth of the city4 ,the population of a great commercial city must be congested near the business center4 ,this is a necessary condition of its existence4 ,all that can be done to meet this condition is to provide all possible facilities for moving the people into and out of the business districts and within its limits4 ,during recent years the business population of the lower part of the ,borough of ,manhattan has become greatly congested4 ,very high buildings1 providing business accommodations for large numbers of people1 have been constructed1 and these people must move to and from their working places at about the same times1 that is1 at the rush hours in the morning and afternoon1 at the beginning and ending of the working day4 ,every effort has been made to provide for this immense and rapidly increasing local passenger traffic1 by the construction of surface1 elevated1 and subterranean railways2 but the demand for transportation has increased much faster than the facilities can be provided1 and it is evident that the limit of down-town passenger traffic facilities has been very nearly reached4 ,apparently1 the only remedy for these conditions is the movement of business and the people transacting it up-town or to the ,boroughs of ,brooklyn and ,queens1 which are now readily accessible by tunnels and subways4 ,this movement1 of course1 is resisted by the great real estate and money interests centered in the lower part of the city1 but1 notwithstanding this resistance1 the improvement has commenced and has rapidly advanced4 ,the great retail houses are being established above #bc;d ,street2 the banks and brokers' offices are rapidly appearing around the new business center of the city4 ,the facilities afforded by the telephone and the subway for communication with the money center have doubtless greatly promoted this up-town movement4 ,when the ,pennsylvania ,tunnel ,extension is in operation1 the easiest and quickest way for the passenger to reach the city from ,newark will bring him into the ,pennsylvania ,station at ,seventh ,avenue and #cc;d ,street4 ,the schedule fast time from ,newark to the ,new ,york ,cortlandt ,street ,station is now #be min4 ,this may be reduced to about #ah min4 by the use of the ,hudson ,company's tunnels1 and while this involves inconvenience in changing transportation at ,jersey ,city1 yet it brings the traveler three blocks nearer ,broadway4 ,the time from ,newark to the ,pennsylvania ,station will be about #ag min41 and the trip will be made without change of transportation1 so that1 undoubtedly1 by far the greater part of the ,pennsylvania's passenger traffic desiring to reach the shopping and hotel center of the city will go to the new up-town station4 ,the effect of the ,tunnel ,extension in increasing the volume and rapidity of the up-town movement and the real estate values will be very great2 indeed1 its influence is already apparent1 although the line is not yet opened for traffic4 ,with the extension of the present subway down town on the west side with direct connections to ,brooklyn1 and up town from #db;d ,street to the ,bronx1 with connections to permit convenient transfers between these two straightaway subways--one on the east side and the other on the west side of ,manhattan--the ,pennsylvania ,station will become a great center for receiving and distributing passenger traffic between all the ,boroughs of the ,city and outlying points4 ,the new post office to be established adjacent to the ,terminal ,station will also greatly assist in accelerating the up-town movement4 ,in concluding this account of the ,new ,york ,tunnel ,extension project1 the writer desires to pay a tribute of admiration and respect to the memory of the late ,a4 ,j4 ,cassatt1 ,president of the ,pennsylvania ,railroad ,company1 to whom the conception1 design1 and execution of the project are mainly due4 ,his education and experience as a civil engineer1 his thorough knowledge of all the details of railroad construction1 operation1 and management1 gained by long and varied service1 the directness1 clearness1 and strength of his mind1 and his great executive ability1 placed him at the head of the railroad men of the country4 ,in the consideration of great problems1 whether of transportation1 finance1 commerce1 or political economy1 he was almost unequaled1 owing to the breadth1 originality1 and decisiveness of his character2 yet his manner to his subordinates was so direct and simple that he seemed unconscious of his own superiority4 ,great as it is1 the ,new ,york plan of improvement is only one item in a far-reaching scheme of development which became the policy of the ,pennsylvania ,railroad ,company through ,mr4 ,cassatt's advice and influence1 yet his strongest interest was doubtless centered in the ,new ,york works4 ,it is the sincere regret of all connected with the design and execution of the project that he did not live to see its completion4 ,,footnotes3 ,footnote ,a3 ,brigadier-,general1 ,u4 ,s4 ,army1 ,retired2 ,chairman1 ,board of ,engineers1 ,pennsylvania ,tunnel and ,terminal ,r4 ,r4 ,co4