Engineering Wonders of the World
Volume I

354 ENGINEERING WONDERS OF THE WORLD. which is in use every minute of the day. The crossing is so placed that very frequently The 96th Street Crossover. a train must wait in the sta- tion until the crossing is clear, and this delays all trains on the line, because the following train is held from entering the station. The cost of improving this crossing is estimated at over half a million dollars. In addition, great delays are caused by the long time it takes for passengers to leave and enter trains Delays at Stations. at express stations. The two doors of each car are quite in- adequate for reasonably rapid interchange ; and as a train in a station holds back the following train, the entire system is delayed. The Public Service Commission calculates that these excessive delays cut down the capacity of the Subway by fully one-third. These intricacies of operation have been the subject of as much deep study as the entire original design of the Subway. It is satis- factory to know that two valuable solutions have been worked out. One of them is being applied in the New York Subway, while the other will doubtless find a use in future lines of the same character. The first is the multi-door Multi=door car, having three, four, or Cars. __ . more doors m each side, oper- ated by compressed air from the end of the car. A four-door car, designed for the Com- mission by Mr. B. J. Arnold, and a three-door car, have been tried. Both proved successful. Unfortunately, the curved station platforms hamper their use somewhat. The other expedient is a multi-track station. (Fig. 18 is a design by Mr. * t tt x The Multi- Arnold). Here two or more x ' track Station, tracks are provided for each line track, so that a train need never wait for a station track to be vacated. The several operating difficulties just men- tioned are evidences of the progress made since the New York Subway was first planned, and demonstrate how each new engineering work leads to further tasks and further ad- vances. But it will be evident to the reader that the real solution of the New York Sub- way problem lies in more subways. The city needs them, and must and will build them ; it is already planning actively to do this. Other cities will also build underground rapid transit railways. They are a necessity in the large city of the future. London and Paris already have them on a large scale. Philadelphia, Berlin, and Boston have made a beginning. The elevated railway, once very popular, ruins an entire street with its noise and dirt. Though the subway costs more at first, its ultimate benefits doubtless make it the cheaper in the end. Fig. 18.—SECTIONAL VIEW OF A MULTI-TRACK STATION PROPOSED FOR FUTURE SUBWAYS. Each lino track has two station tracks, so that an approaching train will always find a station track vacant.