340 CHEMISTRY IN AGRICULTURE AND PHYSIOLOGY. 
The Vegetable 
Produces gluten and albumen, 
„ starch, sugar, and oil, 
Decomposes carbonic acid, 
,, water and ammonia, 
Disengages oxygen. 
Absorbs heat and electricity. 
The Animal 
Consumes glutenand albumen, 
i( starch, sugar, and fat. 
Produces carbonic acid, 
„ water and ammonia. 
Consumes ox} T gen. 
Produces heat and electricity. 
Vegetables, then, it is evident, generate the base of the 
matters which animals by assimilation render part of them¬ 
selves. 
You will remember the material -world is composed of 
sixty-one elements, the entire vegetable kingdom of fourteen. 
Now, as animals are all directly or indirectly dependent 
upon vegetables for their nutrition, and since the body of an 
animal possesses no power of forming elements, or converting 
one elementary substance into another, therefore the ele¬ 
ments of which the body of an animal is composed must be 
the elements of its food ; hence it follows, as neither silica nor 
iodine enters into any part of the animal tissues, but twelve 
elements are found essential in the formation of their bodies. 
For the maintenance of life in an animal certain conditional 
circumstances are necessary; the first is the assimilation of 
appropriate matters constituting nourishment, the second a 
continual absorption of oxygen for the generating of heat. 
From the mutual action of these, the one on the other, arise 
all vital phenomena. 
Let us first examine life and nutrition in their simplest 
forms. 
The food consumed by the horse produces two, and only 
two, effects necessary to his existence. These are, first, to 
supply him with that animal heat without which the func¬ 
tions of life would stop ; and secondly, to repair the waste 
constantly taking place in his tissues, that is, in the mechanism 
of his frame. 
The domestic fowl enjoys good health if fed with barley 
and chalk; in due season the hen produces a number of eggs ; 
let us examine one of them; within its thin shell of chalk we 
find a yellow globe (yolk), floating in a transparent fluid 
(albumen), both very simple-looking substances, yet we know 
by the aid of heat alone they are built and fashioned into a 
perfect animal, with bones, tendons, muscles, lungs, heart, 
blood-vessels, skin, and even the finer set of feathers. 
An embryo, as long as it retains its attachment to its 
mother, receives all its nourishment from her blood ; at birth 
the foetus “ inhales the breath of life, 55 oxygen , and now be¬ 
comes an independent being. 
