FOOD. 199 



the proper regulating apparatus. Walther found that rabbits 

 and dogs, when tied to a board and exposed to a hot sun, 

 reached a temperature of 114.8 F., and then died. Cases of 

 sunstroke furnish us with similar examples in the case of man ; 

 for it would seem that here death ensues chiefly or solely from 

 elevation of the temperature. In a case related by Dr. Gee, 

 the temperature in the axilla was 109.5 F.; and in many 

 febrile diseases the immediate cause of death appears to be the 

 elevation of the temperature to a point inconsistent with the 

 continuance of life. 



The effect of mere loss of bodily temperature in man is less 

 well known than the effect of heat. 



From experiments by Walther, it appears that rabbits can 

 be cooled down to 48 F. before they die, if artificial respira- 

 tion be kept up. Cooled down to 64 F., they cannot recover 

 unless external warmth be applied together with the employ- 

 ment of artificial respiration. Rabbits not cooled below 77 

 F. recover by external warmth alone. 



CHAPTER IX. 



DIGESTION. 



DIGESTION is the process by which those parts of our food 

 which may be employed in the formation and repair of the 

 tissues, or in the production of heat, are made fit to be absorbed 

 and added to the blood. 



Food. 



Food may be considered in its relation to these two purposes, 

 the nutrition of the tissues and the production of heat. But, 

 under the first of these heads will be included many other 

 allied functions, as, for example, secretion and generation: 

 and under the second, not the production of heat only as such, 

 but of all the other forces correlated with it, which are mani- 

 fested by the living body. 



The following is a convenient tabular classification of the 

 usual and more necessary kinds of food: 



NITROGENOUS : 



Proteids, as Albumen, Casein, Syntonin, Gluten, and their allies, 

 and Gelatin (containing Carbon, Hydrogen, Oxygen, and Nitrogen; 

 some of them, also Sulphur and Phosphorus). 



