Maiis Food and Dietetics. 39 



carbon — the principal element of vegetable and fatty substances 

 — combines with the oxygen introduced into the system by 

 inspiration, forms carbon dioxide, and evolves heat. Thus we 

 see that the nitrogenous element in food, represented by flesh 

 or animal substances, is required chiefly to perfect the tissues of 

 the body, and to repair their waste ; while the carbonaceous 

 element — represented by vegetable articles of diet, and by fats 

 and oils — is absolutely necessary as fuel to support the silent 

 combination ever at work in the system, and to which is mainly 

 due the generation of vital heat. The production of the 

 muscular power of animals is not so much dependent on the 

 assimilation of nitrogenous food as upon the slow combustion 

 of carbonaceous food. According to this view, the formation 

 of heat by the combustion of carbon, and the final assimilation 

 and nutrition processes generally, are attended with the develop- 

 ment of force, of which the muscles are the instruments, not 

 the producers. Since the slow combustion of carbonaceous 

 food in the process of nutrition is attended with the develop- 

 ment not only of heat but also of force, it consequently 

 appears that more power or force is to be obtained from 

 fat than from meat or muscular tissue. The labourer in 

 the fields when starting for his daily toil, with reason, 

 then, and not alone from motives of economy, provides 

 himself with bread and the fat of bacon. Similarly the hunter, 

 when about to be exposed to toilsome expeditions, supplies 

 himself with heat and force-producing fat. 



After some observations on the chemical origin of food, the lec- 

 turer proceeded to the third branch of his subject, dealing seri- 

 atim with the various food products of the animal and vegetable 

 kingdom and their relative value. With regard to flesh food, ex- 

 perience teaches us that, although the flesh of young animals is 

 more tender than that of old, it is, nevertheless, more resistant 

 to the digestive powers. Veal and lamb, for instance, tax the 

 weak stomach more than beef and mutton. The tissues of young 

 animals, too, are more gelatinous, less stimulating, and of less 

 nutritive value than are the more matured. Again, there is 



