STATICS 131 



the time of the experiment. The digestibility of the food can, 

 of course, be determined at the same time. 



In some experiments, e.g. those of Rosenthal, Atwater, and 

 others, the chamber was fitted with apparatus for recording 

 minute changes of temperature in order to determine the 

 amounts of energy produced by the oxidation. In that case 

 the chamber serves as a kind of calorimeter for living subjects, 

 and it is often called a respiration calorimeter. 



FIG. 9. Pettenkofer's Respiration Apparatus. 



The more important results of the experiments have 

 already been described, but they may be briefly summarised 

 as follows : 



(1) For simple maintenance of the animals without gain 

 or loss of weight, the daily quantities of food must be such 

 as to produce the following amounts of available energy : 



For oxen and horses, 35 kt. per 1000 Ibs. live weight. 

 sheep, 40 kt. per 1000 Ibs. live weight. 



(2) The available energy of the digested fats is the same as 

 the total fuel value (8*5 to 9*4 kt. per lb.), i.e. it is 100 per 



