194 report — 1877. 



incuts at Lincoln ; but its application in this country has been greatly superseded 

 by the later inventions of Mr. Westinghouse, in which compressed air is made the 

 motive power. On the other hand, Smith's Vacuum Brake nas been adopted with 

 advantage in all the trains of the Metropolitan Railway Company ; and it has been 

 so far approved by the Great Northern Railway Company that they have already 

 fitted fifty engines and 168 carriages, aud are preparing to fit more of their stock 

 as fast as they can procure the material. The Great Eastern, Great Western, 

 Manchester, Sheffield and Lincolnshire, Midland, South Eastern, North Eastern, 

 North British, and Lancashire and Yorkshire railways have applied it to a more 

 limited extent, some of them by way of experiment. 



COMPEESSED-AlR BbAKES. 



Of the Compressed- Air Brakes, the system most extensively introduced is the 

 Westinghouse, which in its latest form has been made automatic. 



In this system air is forced under a pressure of about 60 lbs. per square inch into 

 a main reservoir of about 1) cubic feet capacity placed underneath the foot-plate, 

 and a line of tubing extends therefrom throughout the tram. Each vehicle is 

 fitted with a small reservoir and a brake cylinder, the reservoirs and tubing through- 

 out being filled with compressed air at a uniform pressure. By reducing the 

 pressure in the main to a slight extent, valves are opened which permit the air to 

 enter the cylinders and press the brakes home. The severance of the main pro- 

 duces the like effect. 



In the Steel-M c Innes system there are two main-pipes. Each carriage carries a 

 vertical cylinder, with piston and rod to communicate the pressure to the brake- 

 gear, and a small air receiver on its lower end. Receivers, cylinders, and con- 

 necting pipes throughout are kept charged with compressed ah - by means similar 

 to those of the Westinghouse ; and to apply the brakes a differential pressure on 

 the pistons is established by opening a cock which allows the compressed air to 

 escape from above the pistons. The same action follows if the pressure of air in 

 the pipes be relieved by any accidental disconnexion of them. 



The Westinghouse Automatic Air-pressure Brake has been rather extensively 

 adopted on the Midland and the North British Railways ; on the Midland 57 

 engines and 166 carriages have been fitted wdth them, and many more vehicles 

 are in progress of fitting. The North British Company have fitted 15 engines and 

 100 carriages, and purpose increasing the number as may be required. They state 

 that they have adopted this brake as being, in their opinion, the best that has yet 

 been devised. 



The London, Chatham, and Dover, the North-Eastern, the Caledonian, the 

 Glasgow and South-Western, and the Lancashire and Yorkshire Railways have 

 fitted or are fitting up engines and carriages for trial of this form of brake. 



Hitherto the application of Steel and MTnnes' Brake appears to be limited to 

 the Caledonian Railway, where it has been in use for two years on the Edinburgh 

 and Glasgow section. 



The Hydraulic Brakes of Barker and Clarke are worked by water under pressure, 

 conveyed through continuous tubing along the length of the train. The pressure 

 is obtained in Barker's by a double-acting steam-accumulator on the engine ; and 

 in Clarke's by a loose piston, without a rod, resting in its normal position at the 

 bottom of a vertical cylinder, filled with water, fixed under the foot-plate of the 

 engine ; when steam from the boiler is admitted beneath, the water is driven into 

 the tube and thence into the carnage cylinders. In Barker's each carriage is fitted 

 with a pair of cylinders on rams, in Clarke's each carriage carries a single cylinder. 

 The brakes were not arranged in the experimental trains to be self-acting in case 

 of a train parting asunder. 



On the Midland Railway two engines and twenty-six carriages have been fitted 

 with Barker's brakes and are there working ; and it has also been tried on the 

 Monmouthshire section of the Great Western Railway, as also on the Crystal 

 Palace line of the London, Brighton, and South Coast Railway. 



I am not aware that Clarke's Hydraulic Brake has been fitted to any other train 

 than that of the experimental train of the Midland Railway, which was the subject 

 pf trial at Lincoln. 



