616 



Experiments 



considerably, is conveyed through a coil immersed in cold water D, 

 furnished with a reservoir E for the condensed water. 



A cock a makes or closes connection with the pump. 



Another cock c, whose opening can be enlarged progressively, 

 permits one to extract air from the receiver for analysis, to main- 

 tain a current of pure air under pressure, or to obtain a very sudden 

 decompression. The manometer b indicates the pressure. 



