Cable Traction for City 1873, Hallidie, an American inventor, devised a system of cable traction for street-railways which, with some modifications of detail, has been adopted, with good results, in a number of American cities. The elements of this system are an endless wire rope buried in a conduit placed in the centre of the track-rails, which conduit has a continuous longitudinal slot, which comes flush with the sur face of the ground (p. 37, figs. 6-9); a series of supporting rollers for the cable, placed inside the conduit at convenient distances apart (fig. 7); a stationary winding-engine, located, usually, at one of the termini of the line, by which the cable is made to travel in the conduit at a predetermined rate of speed; and a car provided with a suitable lever passing through the bottom of the car and through the slot in the conduit, and haying at its lower extremity a suitable clutch, or " grip," for taking- hold of the travel ling- cable when the car is to g-o forward (fig. 6). The rails are of the ordi nary flat pattern, laid as usual. The conduit is generally oval in section, and is made of cast iron, in sections of fiom 12 tO 15 feet in length, bolted together to form a continuous tube. This tube (laid upon a substantial foundation, sometimes cement) is placed at regular intervals in communi cation with the sewers, to insure suitable drainage, and provided with numerous covered manholes, to permit of inspection.
Cable Roaa's in American system WaS intro duced for the first time in 1873, in San Francisco, California, where the ntnnerous and steep gradients of certain important thoroughfares inter posed serious obstacles to the economical operation of the ordinary horse railway. It was found fully to answer its intended purpose, and others of the same type were established in that city with equal success. From this beginning it has been extended, and at the present time is used in Phila delphia, Chicago, Detroit, Kansas City, and elsewhere. The difference in the topography of San Francisco and Chicago—the one being very hilly, and consequently furnishing many steep grades to be overcome, and the other being nearly on a dead level--speaks well for the practicability of the system under the most diverse conditions, as in both these cities the cable line works satisfactorily. No difficulty is experienced in operating the cable road at all seasons. The usual rate of travel is about six miles per hour, thoup-„,11 on suburban roads this is considerably exceeded. The cable traction system is more economical in operation than the method of animal traction which it replaces, and is free from the obvious objections to the latter on sanitary grounds. It affords one of the most practical solutions of the street-railway problem that has been devised.
Steam ifolors on City experiment has been made at vari ous times to substitute steam as a motive-power for surface-roads in cities, and a number of compactly-built steam-motors have been devised for this special service. Except for suburban lines, however, the use of steam has been almost entirely abandoned on surface-roads within the built-up areas of cities. Aside from the g-eneral objection to the use of locomotives in crowded streets, the plan of using- steam-motors is open to the objection that it renders existing rolling-stock of the surface-roads practically use less, and involves too g-reat an outlay of capital for the substitution of a system whose advantages at best are questionable. On suburban roads
connecting with the street-railway lines steam is very generally used as the motive-power, locomotives (dummy engrines) of small size and power spe cially built for this service being employed.
"Fireless" of mention in this connection is the system introduced in 1875 on a three-mile section of the New Orleans and Carrollton Railway (in the suburbs of New Orleans), in which the locomo tive is charged with steam of the requisite pressure from a supply-boiler at one of the termini. The use of a furnace and fuel is by this means dis pensed with, the locomotive (which can be considerably reduced in size) being charged at the starting-point with steam enough to serve for the round trip. This form of engine was termed the fireless locomotive. The system has been introduced in France by M. Francq, who made certain improvements in the details of locomotive construction, and was put in service in 1879 on a short line of railway between Reuil and with complete success. The system appears to have much to recommend it to the favorable notice of engineers.
cars actuated by compressed air have been successfully adopted for passenger railways in cities. One of the most notable examples of this kind is afforded by the Nantes tram way, a line of about three and seven-eighth miles through Nantes, from Donlon, an eastern outskirt, to Chantenoy, its western terminus. The system employed is that of Mekarski. It was introduced in 1879, and so well answered all the demands of practice that in 1882 one of the metro politan tramway companies of London determined to adopt it on the Cale donian road, which runs from King's Cross to Holloway.
Electric A'ailicays in Cities. —Tile past few years liave witnessed tlte introduction of electricity as the motive-power for city and suburban rail ways, and the details of these electric systems of transmitting power have been so far improved that electric railways are rapidly coming into use upon such lines. For surface-roads in cities and for suburban roads com municating with them the electric system possesses such decided advan tages, if not in economy, at least in convenience, over all others yet pro posed and used, that it appears to be merely a question of a little tittle when it shall entirely supersede them. The first electric railway wag a short experimental line built by Siemens and Halske on the grounds of the Electrical Exhibition held in Munich in ISSo. It is shown on Plate 36 (figs- 3-5.) The FirsI Electric Railzvay for public service was built by Siemens and Halske at Berlin, and was opened in AIay, ISSI, between Lichterfelde and the Cadettenhaus. It is one and six-tenth miles long, with a gauge of 39 inches. In this the current is sent along the insulated rails and actuates an electric motor carried beneath the car, which transmits its motion to the wheels, with which it is connected. On this road a speed of eighteen miles per hour can be attained, although the maximum speed permitted is nine miles.