071 a new Friction Sledge for stopping Railway Trains. 221 



the velocity of the train was so imperfect, that I shall merely state the sreneral 

 results, without attempting to deduce any accurate conclusions from them. 



The weight of the engine and train was about 32 tons, and the sledae 

 7 cwt. The results of this trial are sufficient to prove the great efficiency of 

 the Friction Sledge as a means of stopping a train in motion. 



In order to obtain more accurate results, I determined to experiment with 

 a smgle loaded waggon ; and to measure the velocity with precision, I used a 

 portion of the rails inclined to the horizon, and measured, by means of a pair 

 of chronographs reading to the fifth of a second, the time of describing a given 

 space, when the waggon was made to enter upon the inclined plane with an 

 unknown velocity ; or measured the space traversed by the waggon, when its 

 whole motion took place on the inchned plane. 



The subsequent experiments on the Friction Sledge were conducted as fol- 

 lows :— An inclined plane of about 160 feet, on the rails at the Engine Factory, 

 Eingsend Docks, was selected, at the lower extremity of which the friction 

 sledge was placed, and a loaded waggon was either pushed or allowed to run 

 down the inclined plane, so as to impinge upon the sledge at the bottom. The 

 velocity of impact and the length of the slide were the quantities to be mea- 

 sured, from which all others could be inferred by calculation ; the velocity of 

 impact was measured by noting the time taken by the loaded waggon to pass 

 over a measured space on the inchned plane, or by allowing the waggon to start 

 from fixed points on the inclined plane. 

 O" 



Let 0"00' be a portion of the inclined plane, / the inclination of the plane 



2g 2 



