THE GENERATION OF OXYGEN 



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Mercury bulb 

 or funnel 



To anesthetic 



device or to 



reservoir 







lOTHl.mVUW 



'.IIIIIUUMI. 



Wash 

 borHc 



Fig. 176. A cheap form of apparatus used lor making pure oxygen. Sodium per- 

 oxide^ is placed in the left hand bottle and water is allowed to drop slowly down on to 

 the NaoOo from the mercury bulb above. Oxygen is liberated and at once bubbles over 

 through the water in the wash bottle. In one experiment 74 grams of sodium peroxide 

 generated sufficient oxygen to run a IS kilo dog for one hour. At the end of this period 

 the left hand bottle was exchanged for a second (quart milk bottle) containing a sec- 

 ond 74 grams of sodium peroxide and this again liberated sufficient oxygen to run the 

 animal another hour. In this experiment the closed anesthesia apparatus shown in Fig. 

 116 (see also Fig. 175) was used. It is advisable to use some kind of reservoir to catch 

 the oxygen generated as the rate of liberation cannot be controlled accurately by the 

 addition of the water. 



