106 



ENGINEER'S BRAKE VALVES 



to it to increase its volume; in full release and running positions, 

 main-reservoir air passes through this chamber and through 

 the small holes in the equalizing piston on its way to the train 



pipe, as can be seen by the line of arrows. This valve has an 

 excess-pressure valve in one side through which the air from 

 the main reservoir has to pass when the rotary valve is in run- 

 ning position. 



