AND PHYSIOLOGY. 



179 



325. Voice .of Chemistry —Chemistry, however, teaches 

 us that we can find in the vegetable world all the principles 

 necessary to support the body without using animal food. 

 And although the vegetable kingdom contains those elements 

 which will support life in many instances, yet we know, 

 as a general rale, that we find man in the highest degree 

 of bodily and mental vigor, only when he makes use of 

 a mixed diet. And we also find that all animals which are 

 the most active in their habits, and rapid in their motions, are 

 feeders upon animal flesh. There is also a race of half civil- 

 ized savages, the Guanchos, who spend the greater part of 

 their lives in the saddle and constantly in a state of great 

 activity, who live almost exclusively upon animal diet, and 

 yet are unequaled in their powers of physical endurance, and 

 live lives fully equal to the average in duration. 



326. Argument from the Teeth. — The strongest physio- 

 logical argument in favor of a mixed diet, is found in the 

 conformation of the teeth and alimentary canal of man. In 

 those animals which live exclusively upon animal diet, the 

 teeth are sharp and pointed, with a very short alimentary 

 tube, since the nutrient portion of the food is readily absorbed 

 by the lacteals. On the other hand, the teeth of vegetable 

 feeding animals are smoothed upon their upper surfaces, being 

 adapted to crush vegetable substances, and the alimentary 

 tube very long, since the nutrient portion of vegetable food is 

 not so readily parted with. Now in man we find neither of 

 these apparatuses perfectly complete, but an admixture of 

 both. Part of the human teeth are of the carnivorous or 

 flesh eating kind, and another part of the herbivorous or 

 vegetable eating kind : but each of them so modified, that 

 either kind of food can be readily prepared for digestion. 

 The alimentary canal too is intermediate between that of the 

 carnivorous and herbivorous type, being equally well adapted 



325. What does chemistry teach on this subject? How does great bodily activity 

 affect the diet as illustrated by the Guanchos ? 326. State the argument derived from 

 the teeth. What two kinds of teeth are found in man ? 



