Page:Encyclopædia Britannica, Ninth Edition, v. 20.djvu/266

Rh 248 RAILWAY heavier the load for which mineral vehicles are constructed, the greater is the tear and wear of the stock, insomuch that the waggons on that line which stood to their work best were the old 6-tou waggons. Recent Railway carriages are composed of two distinct parts, the under- carriage frame or substructure, and the body or superstructure. The under- stock, frame has to carry the body and to resist the stress of work. It should be on axles placed well apart, and should be firmly framed together, of hard wood, with iron tie-rods, brackets, knees, straps, bolts, and nuts. Powerful laminated springs are lodged within the frame to take the pull of the train through the central draw- bars and to intercept and absorb the thrusts of the buffers at the ends through the buffing -rods. On the Midland Railway four- wheeled carriages are (1885) being gradually superseded by six- wheeled and long bogie carriages. Four varieties of bogie carriage and three varieties of six-wheeled carriage are constructed for the service. First-class compartments are constructed to scat MX persons, three on each side ; third - class compartments seat ten persons, five on each side. A uniform width of 8 feet outside, or ?i inside, is adopted for all carriages; and, as a rule, first-class compartments are 7 feet long between the partitions, and third- class compartments 6 feet long. The roof is 7 feet 4 inches above the floor at the centre, and the clear height of the doorway is 6 feet. The wheels are 3 feet 7 inches in diameter. Leading par- ticulars of the several kinds of carriage now constructed on the Midland Railway are given in Table XXX. as follows : Carriage. Length of Body. Compartments. Number of Passengers. Weight Price. 6- wheeled bogie composite Feet. 54 3 first class. 4 third class, 1 luggage 8 x 58 Tons. cwt. 23 1097 4-wheeled bogie composite 45 3 3 ,, 1 = 7 48 18 10 768 4-wheeled bogie third class 43 7 third class 70 17 15 620 40 2 first class, 3 third class, 1 luggage 6 42 17 5 654 6-wheeled first class -30 4 first class 24 10 13 516 31 2 first class, 2 third class, 1 luggage 5 32 11 10 450 6-wheeled third class 31 5 third class 50 10 7 390 Each of these carriages is fitted with a vacuum brake. In the beginning of 1885 there were 837 bogie carriages at work on the Midland Railway, inclusive of 34 Pullman cars. The bogie cars, in virtue of their ability to swing their bogies to the curves on the line, run more freely than ordinary carriages, which have parallel axles. Six-wheeled carriages are enabled to run the more freely by an allowance of lateral play for the axle-boxes of the middle axle between the axle-guards, whereby the wheels adapt themselves freely to the rails on curves. The Pullman cars in use on the Midland Railway were sent from America. They are of two kinds, the drawing-room for day service and the sleeping-car. The body of the cars is 51 feet in length externally and 8 feet 9 inches wide. Inside the body is 8 feet 2 inches wide, and 8 feet 6 inches high above the floor. The total length, including the gangways at the ends, is 58 feet. Each car is mounted on two four-wheeled bogies. There are seats for twenty-seven persons in the drawing- room car, with lavatories and heating apparatus, and twenty-two beds are made up in each sleeping-car. The cars weigh 21 J tons and their cost is 2700 each. The carriage stock of the Metropolitan Railway was designed to carry large numbers. The bodies of the carriages are 39^ feet in length and 8 feet wide outside, running on eight wheels, of which the extreme axles radiate, or are movable laterally to suit the curves of the way. The first-class carriages are divided into six compartments, providing seats for forty -eight passengers. The second and third class carriages have eight compartments, hold- ing altogether eighty passengers in each. These carriages weigh 13 tons each. The waggon stock of the Midland Railway is of several classes. All the standard goods and mineral waggons, as well as cattle- waggons, are constructed to carry 8 tons. Leading dimensions, weights, and prices are given below in Table XXXI. : Waggon. External Di- mensions over Corner Pillars. Internal Dimensions. Load to carry. Weight of Wag- gon. Price. Length. Width. Length. Width. Height above Floor. Covered goods -iigh - sided for goods or coal Low-sided. . Cattle wag- gons ft. in. 14 11 14 11 14 11 13 6 ft. in. 7 5 7 5 7 5 8 ft. in. 14 2 14 6 14 6 17 9 ft. in. 6 10 7 7 7 4 ft. in. 5 lOJ 2 10 1 9 7 OJ tons. 8 8 8 8 tns. cwt. 5 3 5 2 4 14 6 & 72 68 61 86 The covered goods waggons are made with a doorway at each side, 5 feet wide and 5 high, and a sliding door to each door- way. The high -sided waggons are made with a doorway and hinged door in each side, and two trap-doors in the bottom. In the low-sided waggons each side is a door for its whole length. The cattle-waggons are made with doorways in each side, to each of which there are two doors hinged to each doorpost, and a letting- down door hinged to the lower side-rail. All the waggons are fitted with transverse buffing and draw springs. Lighting. Lighting of Carriages. The North London Railway Company, it is believed, were the first to use gas instead of oil for lighting carriage stock. Thirty gas-lights in a train are supplied from two reservoirs or gasholders in the brake-vans, which hold 200 cubic feet of ordinary coal-gas, supplied from the mains, enough to serve the train for from two hours to two and a half hours. The gas is conducted by pipes over the roofs of the carriages, with a branch to each compartment. Ordinary coal-gas has also been used on the metropolitan railways. Pintsch's system of lighting carriages by compressed oil-gas is extensively in use on Continental railways, where it has been in operation for upwards of ten years. In 1876-77 the system was tried successfully on the Metropolitan Railway, when it appeared that 1000 cubic feet of the compressed gas could do the work of 6500 cubic feet of coal-gas, at a cost of scarcely one farthing per burner per hour, against one-third of a penny for coal-gas lamps, and from ^d. to fd. for oil-lamps. The gas is distilled from cheap oils, as the waste - products from the manufacture of paraffin, soft lignite, or shale. The gas is pumped from the gasholder into reservoirs, in which it is compressed to about one-tenth of its ordinary volume. From these it is drawn off into a reservoir stowed under each carriage at a pressure of six atmospheres, or 90 ft per square inch. The Pintsch system is in use on railways in England and Scotland on nearly 3000 vehicles, and is being extended to other stock ; the number of vehicles thus lighted in all the railways of Europe is about 18,000. Besides, the system is employed for the head-lights of locomotives. Intercommunication signals for railway trains are provided Inter between driver and guard, driver and passengers, or passengers com- and guard. Electric means of communication have been proposed muni and tried, but mechanical appliances are most commonly employed, tion There is the ordinary guard's cord, extending along the train out- signa side, placed so as to be accessible from the window ; then there are the same cord, with an attachment coming inside the window, the English cord, connected with a bell in the driving cab, a line inside the carriage connected with the steam-whistle, and so on. The acoustic signals appear to belong to the last type ; but none of these systems is comparable with the through middle passage of the American cars already noticed. Continuous Brakes. No department of railway practice has in Con- recent years received closer attention and more minute study than tintu that of continuous brakes, brakes applied to the several vehicles brak in a train. With the amount of brake-power that had for many years been supplied to passenger trains hand-brakes on tenders and guards' vans a train running at from 45 to 50 miles per hour on a straight level line could not be pulled up within from 800 to 1200 yards ; and even that inadequate amount of brake-power was in the hands of several men. It was clear that the problem of arresting a train in the shortest distance could only be solved by bringing a power to bear on every part of the train in the shortest possible time. But the difficulty consisted in establishing con- tinuity of action, so that the engine-driver or the guard should be enabled to apply the brake-blocks on a series of vehicles in one operation. Mechanical means were first tried, in the systems of Fay and Newall, in which the brakes are worked by a continuous rod passed under the vehicles. These systems were found to be available only on sections of not more than four or five vehicles, and were not worked by the driver but by the guard. In Septembei 1858 a circular was issued by the Board of Trade to the railway companies, calling attention to the advantages to be derived from having their trains controlled by a sufficient amount of brake-power. Subsequently many inventions were tried, brakes worked by fluid pressure, others worked by chains ; but no practical solution of the problem appears to have been arrived at until Mr Westinghouse of Pittsburgh, U.S.A., invented a really continuous brake worked by compressed air, which was quickly adopted in the United States, and was tried a few years later on several .railways in England. It is still (1885) employed exclusively on the Metropolitan District Railway. Although the Westinghouse brake was greatly in advance of previously existing systems and answered ordinary requirements