CHEMICAL CONSTITUENTS :—ALBUMEN. 31 
Chemical Constitution of the Animal Body. 
13. By far the larger proportion of the Animal fabric is 
formed at the expense of the substance termed Albumen ; the 
composition and properties of which, therefore, claim our 
first attention. The fundamental importance of albumen in 
the animal economy, is shown by the fact that it constitutes, 
with fat, and a small proportion of certain mineral ingredients, 
the whole of that mass of nutrient material stored up in the eggs 
of oviparous animals, which, being appropriated by the germ 
to the building up of its fabric, is converted by it into the 
bones, muscles, nerves, tendons, ligaments, glands, mem- 
branes, &c. of the embryo. We find it also constituting a 
large proportion of the solid matter of the blood and other 
nutrient fluids of the adult animal ; and it is the fundamental 
form to which the various azotized substances employed as 
food (§ 153)—such as animal flesh, or the gluten of bread— 
are first reduced by the act of digestion. It is composed 
of 49 carbon, 36 hydrogen, 14 oxygen, 6 nitrogen, with a 
minute proportion of sulphur ; it is generally blended, also, 
with more or less of fatty matter, and with saline and earthy 
In the animal fiuids it exists in its soluble 
; and is united (as an acid to its base) with about 13 
‘considerable quantity of it exists in a fluid (as in the white of 
athe egg), it gives to it a glairy tenacious character ; but it is 
early tasteless. When such a fiuid is exposed to a tempe- 
ature of about 150°, a coagulation or ‘setting’ takes place, as 
in the familiar process of boiling an egg. But if the albumen 
2 present in smaller quantity, the fluid does not form a 
sistent mass, but only becomes turbid ; and this only after 
ing boiled. Albumen which has been dried at a low 
perature, however, may be heated to the boiling point of 
ater, without passing into the insoluble condition ; a fact 
hich is of peculiar interest in relation to the power which 
2 Tardigrada (Zoow. § 841) possess, of sustaining a very 
gh temperature without the loss of their vitality, when 
