108 OF FOOD. 



it, is also necessary for the perfect nutrition of the body that fat be 

 supplied, under its own form, with the food. For the human 

 species, also, it is natural to have them both associated in the 

 aliment' .ry materials. They occur together in most vegetable sub- 

 stances, and there is a natural desire for them both, as elements of 

 the food. 



They are not, however, when alone, or even associated with each 

 other, sufficient for the nutrition of the animal body. Magendie 

 found that dogs, fed exclusively on starch or sugar, perished after a 

 short time with symptoms of profound disturbance of the nutritive 

 functions. An exclusive diet of butter or lard had a similar effect. 

 The animal became exceedingly debilitated, though without much 

 emaciation; and after death, all the internal organs and tissues 

 were found infiltrated with oil. Boussingault 1 performed a similar 

 experiment, with a like result, upon a duck, which was kept upon 

 an exclusive regimen of butter. " The duck received 1350 to 1500 

 grains of butter every day. At the end of three weeks it died of 

 inanition. The butter oozed from every part of its body. The 

 feathers looked as though they had been steeped in melted butter, 

 and the body exhaled an unwholesome odor like that of butyric 

 acid." 



Lehmann was also led to the same result by some experiments 

 which he performed upon himself for the purpose of ascertaining 

 the effect produced on the urine by different kinds of food. 2 

 This observer confined himself first to a purely animal diet for 

 three weeks, and afterwards to a purely vegetable one for sixteen 

 days, without suffering any marked inconvenience. He then put 

 himself upon a regimen consisting entirely of non-nitrogenous sub- 

 stances, starch, sugar, gum, and oil, but was only able to continue 

 this diet for two, or at most for three days, owing to the marked 

 disturbance of the general health which rapidly supervened. The 

 unpleasant symptoms, however, immediately disappeared on his 

 return to an ordinary mixed diet. The same fact has been esta- 

 blished more recently by Prof. Wm. A. Hammond, 3 in a series of 

 experiments which he performed upon himself. He was enabled 

 to live for ten days on a diet composed exclusively of boiled starch 

 and water. After the third day, however, the general health began 



1 Chimie Agricole, p. 166. 



2 Journal fur praktische Chemie, vol. xxvii. p. 257. 



3 Experimental Researches, &c., being the Prize Essay of the American Medical 

 Association for 1857. 



