THE CHEMISTRY OF THE KITCHEN. 361 



deprivation of food is not fatal for a considerable time, 

 varying Avith internal and external conditions and influences. 

 Man requires food to build up his organism, repair its 

 waste, maintain its nutrition, generate heat and evolve its 

 dynamic energies. The necessity or demand for food is 

 manifested by sensations of hunger, discomfort and debility. 

 Its supply is influenced and very largely controlled by the 

 inexorable demands of the palate, an organ of sense, — 

 the endowment of nerves distributed upon the tongue. 

 Placed at the very gateway of life, it refuses to pass sub- 

 stances irritating, acrid and injurious without its protest, 

 and impels the individual to select such food materials as are 

 acceptable to its requirements, which, fortunately, are usually 

 those essential to the necessities and intes-ritv of the orffan- 

 izatiou. 



" Now good digestion wait on appetite and health on both." — 

 Macbeth. 



Man selects his food from animal and vegetable sources, 

 influenced in his choice by peculiarities of race, climatic 

 conditions and the refinements of civilization. The source 

 of all our foods is in the veo-etable kingdora. Vegetable 

 products have the power of selecting and incorporating into 

 their tissues such inorganic mineral elements as are needed 

 for the growth and nutrition of animals, thus lurnishing a 

 complete food. Therefore animal tissues are but another 

 form of vegetable tissues ; and as vegetation is impossible 

 without the influence of the light, heat and energy of the 

 sun, therefore the sun is the source of the force or energy 

 which we call life ; and as matter is indestructible, so also is 

 the life-force indestructible, however produced or mani- 

 fested. 



Food in its relation to the animal system, as a source of 

 power, is the same as that of coal to the steam engine. The 

 food must pass through the process of oxidation in the 

 animal economy to be converted into actual energy, such as 

 muscular and nervous power and animal heat ; so likewise the 

 coal must be oxidized in the locomotive, and converted or 

 reconverted into potential energy through the expansive 

 property of steam. 



