OF DENISON UNIVERSITY. I - 



ceiver now rests on the bottom of the water jar and enough water re- 

 mains in the water jar to protect the open end of the receiver and ex 

 elude the air. 



To get the vital capacity, fill the lungs with the largest possible 

 inspiration, place the tube to the mouth, open the clamp and empty 

 the contents of the lungs into the receiver, at the end of the greatest 

 possible expiration, close the clamp, read off the volume of air in the 

 receiver, from the scale. 



When the first air is sent into the receiver from highly inflated 

 lungs it is under some pressure whicli is about balanced by the weight 

 of the water in the receiver, but when the water in the two vessels is 

 at the same level, if more air is sent into the receiver it finds little or 

 no resistence, as the weight then begins to act to support the weight 

 of the receiver. 



To determine the three factors of the vital capacity of the lungs, 

 the experimenter should be seated and should time his regular resj)ira- 

 tory movements and should use the receiver about half full of water 

 in order to obviate suction or resistance as much as ])ossible. 



It was found by the use of this instrument that the vital ca- 

 pacity of the class was a little above the average and that by blowing 

 the vital capacity regularly twice every day those students whose vital 

 capacity was far below the average at the start, could be brought uj) 

 to above the average in the course of two or three weeks. It is rec- 

 ommended as a simple, cheap, and convenient lungstrengthener. 



