_Viaduct._--A considerable portion of the double-track branch lines north of 103d St. is viaduct, or elevated structure. The viaduct construction on the West Side Line extends, including approaches, from 122d St. to very near 135th St. Of this distance, 2018 ft. 8 ins. are viaduct proper, consisting of plate girder spans carried by trestle bents at the ends, and by trestle towers for the central portion. The columns of the bents and towers are built-up bulb-angle and plate columns of H-section of the same form as those used in the bents inside the subway. The approaches proper are built of masonry. The elevated line proper consists of plate girder spans, supported on plate cross girders carried by columns. _Stations._--Many stations are built along the line. These are located on each side of the street. The entrances at the stations consist of iron framework, with glass roofs covering the descending stairways. The passageways leading down are walled with white enameled bricks and wainscoted with slabs of marble. The stations for the local trains are located on each side of the road close to the walls, since the outside tracks are reserved for the local trains, while the middle ones are reserved for the expresses. The few stations for the express trains are located between the middle and outside tracks. Stations are provided with all the conveniences required, having toilet rooms, news stands, benches, etc., and are lighted day and night by numerous arc lamps. _General._--The contractor completed the work in four years. No difficulty was encountered in doing this, since the great extension of the road and the great width of the avenues under which it runs allowed work all along the line at the same time. The work, briefly summarized, comprises the following items:-- Length of all sections, ft. 109,570 Total excavation of earth, cu. yds. 1,700,228 Earth to be filled back, cu. yds. 773,093 Rock excavated, cu. yds. 921,128 Rock tunneled, cu. yds. 368,606 Steel used in structure, tons 65,044 Cast iron used, tons 7,901 Concrete, cu. yds. 489,122 Brick, cu. yds. 18,519 Waterproofing, sq. yds. 775,795 Vault lights, sq. yds. 6,640 Local stations, number 43 Express stations, number 5 Station elevators, number 10 Track total, lin. ft. 305,380 „ underground, lin. ft. 245,514 „ elevated, lin. ft. 59,766 In addition to the construction of the railway itself, it was necessary to construct or reconstruct certain sewers, and to adjust, readjust, and maintain street railway lines, water pipes, subways, and other surface and subsurface structures, and to relay street pavements.