494 DU. PROUT ON ANIMAL CHEMISTRY. 
Curdy a well-known substance found in the milk of all animals, 
is another variety of the albuminous principle. 
In considering the relative nutritive powers of this class of 
bodies, it is necessary to take the azote into account; and if we 
reckon this last as equivalent to carbon, which, for a rough com¬ 
parison, may perhaps be fairly done, we shall find that albu¬ 
minous bodies lie, in this respect, between the saccharine and 
oleaginous groups—that is to say, they contain from sixty-five to 
eighty-one per cent, of carbon and azote; gelatine containing the 
least, and curd the greatest proportions of these two elements. 
The general conclusion from the whole taken together, in a nutri¬ 
tive point of view, is, that substances containing naturally less 
than thirty, or much more than eighty per cent, of carbon, are 
not well, if at all, adapted for alimentary purposes. 
There is a point of considerable importance connected with this 
subject, which, before we proceed, may be briefly noticed. We 
have seen that all the substances used by man as aliments, with 
the exception of sugar and alcohol, are merorganized bodies. We 
have also stated that no crystallized, or crystallizable body seems 
capable of forming a constituent part of a living organized being. 
The question therefore arises, whether pure sugar, so much used 
as an aliment, is really not the very worst form in which the sac¬ 
charine principle can be taken. Alcohol, in its pure state, has 
been long generally admitted to be its worst form; and I am de¬ 
cidedly of opinion, that in subjects labouring under those forms of 
dyspepsia connected with deficient merorganizing power, which 
are by far the most frequent, pure sugar is as difficult to assimi¬ 
late as pure alcohol, and little less injurious. Indeed, the best 
argument in favour of this opinion is, that it is actually used in 
moderate quantity only, and as a condiment, and cannot be taken 
in the same manner and quantity in which its merorganized pa¬ 
rallel, starch, is taken, which, as is well known, constitutes one 
of the most general and abundant articles of food. So alcohol, 
as it exists in wine, in a sort of merorganized condition, can, as is 
well known, be taken in large quantity, and for a great length of 
time together; while, if so taken in its pure state, it would in¬ 
toxicate, or lead to disorganization. The same remarks apply to 
oily bodies, which in their pure state, and especially in their fluid 
state, are exceedingly difficult of assimilation; but in the state of 
emulsion, or that mixed state in which they occur in natural fats, 
or in butter, they are much more easily disposed of, and there 
are few stomachs that will not bear a small portion of them. 
The question next to be considered is, can animals live on one 
of these classes of alimentary matters exclusively, without partak- 
