Liquefaction of Gases. 205 



(c) The iron flask, 3 litres in capacity, containing liquid 

 ethylene, under high pressure. 



Fk. 3 



(d) A zinc vessel with ice. 



(e) The condenser, for cooling ethylene by means of ether 

 and solid carbon dioxide. 



(/) The cock connecting the condenser with the small 

 pump. 



(g) The cock serving to let liquid ethylene into the 

 vessel b. 



(A h') Iron flasks, 10 litres in capacity, containing oxygen 

 or air under a pressure of 100 atm., connected by means of a 

 tube with the manometer i and the cylinder a. 



(k) The glass vessel with triple walls, serving to receive 

 liquid oxygen or air under atmospheric pressure. 



