DIGESTION. 589 



themselves to it have enjoyed good health for years. Indeed 

 in some parts of the world, Hindostan for example, animal food 

 is abstained from on account of a religious scruple, and yet the 

 inhabitants enjoy health. 



Wheat flour seems one of [the most nourishing articles of 

 vegetable food. In the northern parts of India, where the popu- 

 lation live upon wheat, the inhabitants are said to be a stouter 

 and more hardy race than those who live in the south, where 

 the food is rice. But perhaps other circumstances besides the 

 different quantity of nourishment in wheat and rice may intervene 

 to constitute this difference. 



We have a number of interesting experiments by Sir Astley 

 Cooper, on the relative digestibility of various articles of food. 



To understand the way in which these experiments were made, 

 it is necessary to state that the food in the stomach is dissolved 

 in the gastric juice, and that the difficulty of digestion is consi- 

 dered as proportional to the length of time which elapses before 

 the food in the stomach is dissolved. If, therefore, we put a giv- 

 en weight of any food into the stomach of an animal, allow it to 

 remain a certain time and then weigh it again, it is clear that 

 the food which weighs least will be the most digestible. Sir 

 Astley Cooper made his experiments on dogs. Given weights 

 of the respective articles were put into the stomach of the dog. 

 After a certain interval he was killed, and the proportion remain- 

 ing undissolved in the stomach determined. Raw food and the 

 lean parts only of meat were given, except when the contrary is 

 expressed : 



Experiment 1st. 



Kind of food. 



Pork, 

 Mutton, 



Button, 

 Beef, 

 Veal, 

 Pork, 



Pork, 

 Mutton, 

 Beef, 

 Veal, 



