CONTINUOUS BAILWAY BRAKES. 181 



air within tho cylinder, wliicli is tlie same as that without 

 the cylinder. 



To apply tho brakes, this equilibrium is destroyed in the 

 following way : a jet of steam is blown through the ejector, 

 which draws the air from tho continuous train pipe and 

 the cylinders it connects ; those, being exhausted of air, 

 collapse vmder the pressure of the external air, and apply 

 the brakes. 



This brake does not comply with the Board of Trade 

 requirements in several respects. 



(a) It is not instantaneous in action. It cannot be 

 applied by the guard. 



Tho brake is efficient in stopping trains so long as there 

 ia no leakage in the pipes or cylinders to neutralize the 

 action of tho ejector. 



{b) In case of accidental parting of the train, or in the 

 case of derailment, the brake is useless. 



The l)rake does not command the driver's oonfidonco, as it 

 is unreliable. The brake is an example of Class III. 



The " IlAKDY " Bkake 



Resembles Smith's. Two ejectors are used, one of which 

 exhausts the cylinders on engine and tender, the other acts 

 on tho continuous train pipe, and exhausts the cylinders 

 on tho carriages. It would be more correct to describe the 

 ejector as double, than as two. Tho cylinders differ some- 

 what from " Smith's " ; their lower ends are open to the 

 air, the piston fits loosely, and is made air-tight by moans 

 of an elastic diaphragm, the outer edge of which is bolted 

 between the flanges of the cylinders, which are cast in two 

 halves, tho inner edge being fitted to the piston to exclude 

 the air. 

 The action of tho brake is identical with " Smith's." It 



