260 PROFESSOR LIEBIG ON THE AZOTIZED 
the sugar is decomposed into carbonic acid and alcohol, and not 
into lactic acid and mucous matter, as is the case when common 
caseum or fresh lactate of caseum is used. 
It is well known that fermentations may be produced in saccha- 
rine solutions by more than one substance. Vegetable casein 
cannot be considered as the basis of yeast ; but the circumstance 
of the juice of grapes not coagulating when boiled, and entering 
again into fermentation when allowed to stand, seems to prove 
that it does not contain vegetable albumen, as this body is well 
known to be entirely changed by boiling, even when the solu- 
tion is so dilute that the coagulum cannot precipitate itself. 
Another inquiry must, of course, be made into the properties 
of all these bodies, and I wish it distinctly to be understood that 
such is not the intention of the present paper; my desire is to 
call the attention of physiologists and physicians to the fact 
that the composition of azotized vegetable nutriments is the 
same as the constituents of animal bodies, and when this is 
proved, no doubt can be entertained as to the similarity of the 
process of nutrition, in graminivorous and carnivorous animals. 
A carnivorous animal may be said to feed on what is in no 
way different from itself; it adds a piece of muscle, as it were, to 
its muscle: a graminivorous animal may be said also to do the 
same, because the food it consumes has the same composition 
with its own flesh and blood. 
The flesh and the blood, the food of carnivorous animals, 
assumes precisely the same form in their organization as the 
vegetable casein, albumen, and fibrin in graminivorous animals. 
In this sense, then, we may assert that vegetables generate 
the blood of animals, although physiologists cannot make use of 
this expression, however correct, chemically speaking, on account 
of the different states in which these ingredients are found in 
the vegetable and animal kingdom. 
It is really a very remarkable circumstance, that the inorganic 
ingredients also are the same in both; magnesia, phosphoric 
acid, lime, iron, alkalies, and sulphur, are constantly found in 
them ; both leave, when burnt, similar ashes. 
Animals are distinguished from plants by their capability of 
moving from place to place, by their sensations, and sensibility, 
or, in one word, by their senses; for all these purposes certain 
organs are required, which are entirely wanting in plants; still, 
the same active principle gives to the bud, the leaves, and the 
