148 



BENEDICT— THE IXFLUEXCE OF 



[February 4, 



be breathed over again, but before entering the chamber, the defi- 

 ciency in oxygen is made up by admitting pure oxygen out of a steel 

 cyHnder, such as is used by a physician at the bedside. 



It is possible with an apparatus of this type, then, to determine 

 how much carbon dioxide and water are produced in twenty-four 

 hours and how much oxygen gas is absorbed. If, together with 



RESPIRATION CHAMBER 

 used 



*^'° } produced 



deficient 



. CO. I — I H^o 



absorbed bvi obsorbed by 



n_ 



Fig. I. Schematic outline of ventilation system in the respiration calorimeter 

 at Wesleyan University, Aliddletown, Conn. 



these data, we have the analyses of the urine and the feces, it gives 

 us a very perfect picture of the transformations that have taken 

 place inside the body during the period the subject has been inside 

 the respiration chamber. 



With the boiler, this is about as far as we can ordinarily go, as 

 there is no satisfactory method for measuring the total amount of 

 heat given off by the boiler in a large power house, but with a man 

 it is possible to measure not only the products of combustion and 

 the oxygen consumed but also to measure directly the amount of 

 heat produced by the oxidation or combustion of the substances 

 inside the lx)dy. This is the calorimetric feature of the apparatus. 

 The air-tight copper box is surrounded by a number of cases which 

 gives it a refrigerator type of construction and provision is made 

 for the prevention of any loss of heat through the walls. There 

 being no loss of heat, the man, acting as a small furnace, would 

 soon produce enough heat to make him very uncomfortable. An 

 ordinary man at rest gives off about as much heat as a 32 c.p. 



