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formed in the animal body from starch, and tliat gelatin is formed 

 in it, probably from albumen, it is certain that the term assimilation, 

 in the physiology of animals, cannot be restricted to the mere selec- 

 tion and appropriation of compounds already formed in vegetables 

 (as Dumas supposes), but must include, also, certain processes of 

 transformation (as maintained by Dr Prout). And admitting that 

 the question, as to the actual formation of albumen in animals, can 

 only be finally decided by ascertaining whether the whole quantity 

 of azote thrown off from an animal in a given time is greater than 

 is introduced into it in the form of albuminous ingesta, ho urged 

 various reasons for inclining to the opinion, that a certain quantity 

 of albumen is formed, chiefly from the anylaceous ingesta, in the 

 animal body. 



He admitted, however, that a comparison of the proportion of 

 the elements in the azotised aliments, and in the excretions, shews 

 that the formation of albumen in the animal frame must be to a very 

 small extent only ; and stated that the general distinction of the 

 azotised, or the chief nutritious portion of the aliments, and the 

 non-azotised or chiefly calorific portion of them, and the doctrine of 

 these last protecting the albuminous part of the blood, and the tex- 

 tures fi'om the agency of the oxygen taken into the blood, and that 

 of the wasting of the textures, and death by anoemia in weakening 

 diseases, being due to the action of the oxygen, appear to him to be 

 quite consonant with clinical observations in various diseases, and to 

 be an important addition to pathology ; besides giving us more pre- 

 cise ideas as to the nature of the function of digestion, and the law 

 of Prout, of the necessity of mixture of aliments for the support of 

 animal life. This doctrine is the strongest illustration of what was 

 formerly stated as to the use of the oxygen taken into the animal 

 body, viz., — not to take any direct part in the formation of com- 

 pounds by strictly vital affinities, but to exert a simply chemical 

 action on all organic compounds capable of yielding to simply 

 chemical affinities, and so to support the excretions. 



The formation of gelatin in the living animal body, he considered 

 as certainly owing to the separation of carbon and hydrogen, by help 

 of the oxygen of the air ; but pointed out the possibility of this 

 taking place, not merely, as Liebig states, from the action of the 

 oxygen on the elements of albumen, but likewise from its action on 

 the elements of starch with ammonia, provided that a certain quantity 

 of oil or fat is formed at the same time. 



