Control of Temperature. 345 



much as they can convert economically into flesh and milk 

 and warm quarters must make the demand for food less. 



It has been found with man that when fasting and at rest 

 under a temperature of 90 F. he consumed 1,465 cubic 

 inches of oxygen per hour, but under the same conditions 

 except a temperature of 59 F. the amount of oxygen was 

 13 per cent, greater and the amount of carbon dioxide given 

 off also 13 per cent, greater, showing that a higher rate of 

 consumption of food in the body was maintained and hence 

 that the man would be required to eat more. 



It is with the cow and fattening animals as it is with a 

 threshing machine, it requires a higher rate of waste of 

 energy to run the machine rapidly than it does to run it 

 slower, but the saving in time of all employed to manage 

 the machine more than pays for the greater waste. So the 

 cow may require an extra amount of food for temperature 

 maintenance to overcome the cooler quarters but she is 

 likely to eat enough more food to enable her to make more 

 milk and a higher profit when all items of expense are taken 

 into account. 



With animals on simply a maintenance ration the aim is 

 to carry them with the least amount of food and hence in as 

 warm quarters as will be healthful. 



It seems likely that the best temperature surroundings 

 for animals being crowded will be found between 40 and 

 50 F. and for animals upon maintenance rations from 50 

 to. 65 or even 70 F. 



423. Heat-Proof Construction Impossible. No enclosure 

 or building can be so constructed that all the heat it con- 

 tains will be prevented from escaping. If it is kept above 

 freezing through cold winters there must be within the en- 

 closure a source of heat. So, too, no enclosure or building 

 can be so thoroughly made as to exclude all heat and hence 

 it is impossible to build a "cool room" which will not get 

 warmer during the summer unless it contains some means 

 of removing the heat which enters. 



The out-door root cellar which does not freeze during 



