Purchased Food, and of its Residue as Manure. 
205 
to get, at least, some insight into their characters, and affords 
useful hints to the stock-feeder in the selection of the most 
suitable food which he may require for fattening stock, as well 
as for working-horses or milch-cows. 
In oilcakes, corn, hay, roots, and most articles of food, we find 
the following groups of food-constituents : — 
1. Nitrogenous, or albuminous compounds, as flesh-forming 
matters. 
2. Non-nitrogenous, or fat and heat-producing compounds. 
3. Mineral matters, or ash-constituents. 
1. The first class includes : 
Vegetable Albumen, a substance identical in composition and 
chemical properties with the white of eggs. 
Gluten, or vegetable fibrine, a compound occurring in con- 
siderable proportions in wheat, and in smaller proportions in 
other cereal grains ; it closely resembles the fibrine of blood and 
the substance of lean flesh and muscle. 
Vegetable Casein, or legumin, a substance identical in compo- 
sition with the casein of milk. Like milk-casein, legumin is 
curdled or precipitated from its solution in water on the addition 
of dilute acids, but is not coagulated like albumen on boiling. 
It occurs in large quantities in peas, beans, lentils, and other 
leguminous seeds. 
The nitrogenous compounds constitute a remarkable class of 
organic substances. They all contain about 16 per cent, of 
nitrogen, and small quantities of sulphur or phosphorus, or both^ 
in organic combination. 
Vegetable albumen, identical in composition and properties 
with animal albumen, may be regarded as the type of this 
important group of compounds, which frequently figure in 
scientific works or in food-analyses under the generic name of 
albuminoids, or albuminous compounds. They are also called 
flesh-forming matters, because they not only closely resemble 
muscular fibre in composition and general properties, but are 
absolutely necessary for the formation of the substance of lean 
flesh. 
Peas, beans, and all leguminous seeds, linseed-, rape-, cotton-, 
and other oilcakes, are rich in flesh-forming matters or albu- 
minoids ; and most cereal grains also contain considerable pro- 
portions of such compounds ; whilst roots, green produce, straw, 
chaff, and similar bulky feeding-materials, are, comparatively 
speaking, poor in albuminoids. 
No food entirely destitute of albuminous compounds is capable 
of supporting life for any length of time, for direct experiments 
have proved, beyond dispute, the fact that the animal organism 
