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BENEDICT— THE INFLUENCE OF 



[Februaiy 4, 



apparatus so that it can be used as external work. This apparatus, 

 the bicycle ergometer, is admirably adapted for the use of the 

 powerful leg muscles and hence we were able to study this to a 

 considerable degree. 



The experiments were made something in this way. The sub- 

 ject was first placed in the respiration chamber for part of a day 

 and the heat production measured during rest, while he was sitting 

 quietly reading a book. This is our " base line," as the surveyor 

 says, or our basis for comparison. On subsequent days similar 



Fig. 3. Bicycle ergometer for studying problems relating to muscular work. 



experiments are made in which the man rides the bicycle ergometer 

 with varying resistance of the electric brake. During these experi- 

 ments the heat production and the carbon dioxide eliminated are 



