]80 



RESPIRATION 



2) Measure the girths of chest and abdomen at end of in- 

 spiration; at end of expiration. 



3) Measure amount of air which you can blow out after 

 deepest inspiration, by blowing through a piece of tubing into 

 a large bottle filled with water and inverted in a pan of water. 



I 



^~ -> 



JJ^ 

 V 



n 



FIG. 105. Apparatus to demonstrate carbon dioxide in expired air a inspiration- 

 6, expiration. 



4) Determine the rate of breathing, that is, the number of 

 inspirations per minute, upon awaking in the morning; upon 

 rising; after dressing; after eating; and after running. 



5) Demonstrate by means of the water-valve respiration ap- 

 paratus (fig. 105) the relative amounts of carbon dioxide in 

 atmospheric air and in expired air, by partly filling bottles with 

 lime water and breathing in and out through mouth tube. 



6) Blow breath through a weak solution of lime water 

 colored with phenolphthalein. 1 



7) Cut open blood clot or piece of liver. 



a) Compare freshly cut surface with surface previously ex- 

 posed to air. 



b) Place freshly cut pieces of blood clot or liver in a bottle 

 containing oxygen. Or 



1 Phenolphthalein is pink in alkaline solutions ; colorless, in acid. 



