76 ALIMENTATION. 



stitial deposits of fat. Poultry, as a rule, is easily digested 

 and palatable, when properly prepared ; but the game-birds, 

 like all other kinds of game, are very decidedly flavored and 

 become distasteful if used as food too constantly. The young 

 white-meated birds form very appropriate articles of diet for 

 persons convalescing from acute diseases. 



Animal Viscera, etc. Although the muscular substance 

 constitutes the most important parts of animals used as food, 

 some of the viscera and other parts are occasionally eaten. 

 The external parts are the feet of pigs and calves and the 

 skin of the calf s head, which are reduced to a gelatinous 

 consistence by cooking. They seem to be easily disposed of 

 by the digestive organs, but are not very nutritious. The 

 pancreas and thymus of the calf (sweet-breads), the kidneys 

 of the calf and sheep, the liver of the calf, of the pig, and of 

 birds, the stomach of the ruminants (tripe), the gizzard, 

 heart, brains, and tongue, all contain organic alimentary 

 principles, nitrogenized and non-nitrogenized, and may be 

 used as occasional articles of diet, but cannot permanently 

 take the place of the muscular tissue. 1 It is a curious physi- 

 ological fact that blood, the fluid which contains materials 

 for the nutrition of all parts of the animal, does not appear 

 to be a nutritious alimentary substance. Payen ascertained 

 this fact, which the universal distaste for blood as an article 

 of food would lead us to suspect, by experiments on pigs. 2 



1 The celebrated pates defoie gras are made of the livers of geese, which are 

 made to undergo hypertrophy and excessive fatty degeneration by confining the 

 animals at a high temperature in a small cage, and stuffing them with food. The 

 pates de Strasbourg are made of these livers, prepared with truffles and other ar- 

 ticles. They are excessively rich, and are ordinarily considered difficult of di- 

 gestion. 



8 Op. cit., p. 129. 



The substance of the bones does not enter, to any considerable extent, into 

 the diet of the human subject, as it does in the carnivorous animals. The exper- 

 iments of Magendie, detailed in the report of the " Gelatine Commission " ( Oomptes 

 Rendus, Paris, 1841, tome xiii., p. 254), showed that dogs can live indefinitely on 

 a diet composed exclusively of uncooked bones. 



