CONTINUOUS BAILWAY BRAKES. 197 



the carriages being moved wken the engine has loft the 

 train at a station, or for shunting purposes. 



The "leak off" device, — which is nothing less than a death 

 ti-ap, — allows the brakes, as before said, to come "off" by 

 themselves, after being applied I'or from 80 to 120 seconds. 

 The dangerous nature of such a device has been often shown 

 when trains have crashed into " buffer stops," owing to the 

 brakes leaking " off," the driver meanwhile believing he 

 had applied the brakes at the right time. The " leak off" 

 device makes the brake quite unreliable. In the event of 

 a train parting when going up a steep bank, the train will 

 be pulled up for a minute, and then allowed to run back- 

 wards to the bottom of tlie bank. In short, it renders the 

 protection conferred by fulfilment of the automatic condi- 

 tion, when really adhered to, futile. 



The " Westinghouse " brake is, like the automatic vacuum 

 brake, provided with a release valve ; but neither of these, 

 the two best brakes in use, are provided with such danger- 

 ous devices as " leak off" holes. 



SUMMARY OF CONCLUSIONS 

 Witji regard to the use of continuous brakes is — 



1. That the use of continuous screw brake and other con- 

 tinuous hand brakes, like Clark's, is declining, and almost 

 ended. 



2. That " chain brakes " are likewise going out, on account 

 of thoir liability to be alfected by the weather, and their 

 rough action. If some device can be invented which will 

 render them reliable in all weathers, they may yet find 

 their place on mineral trains and goods trains, which are at 

 present ill supplied with brake-power. 



3. That by the use of automatic air pressure, or of 

 vacuum brakes, the speed of trains is most effectually con- 



