42 IDENTITY OF ANIMAL 



centrated muriatic acid, 'yielding a solution of an intense 

 purple color. This solution, whether made with fibrine 

 or albumen, has the very same reactions with all sub- 

 stances yet tried. 



Both albumen and fibrine, in the process of nutrition, 

 are capable of being converted into muscular fibre, and 

 muscular fibre is capable of being reconverted into blood. 

 These facts have long been established by physiologists, 

 and chemistry has merely proved, that these metamor- 

 phoses can be accomplished under the influence of a 

 certain force, without the aid of a third substance, or 

 of its elements, and without the addition of any foreign 

 element, or the separation of any element previously 

 present in these substances. 



If we now compare the composition of all organized 

 parts with that of fibrine and albumen, the following 

 relations present themselves : 



All parts of the animal body which have a decided 

 shape, which form parts of organs, contain nitrogen. 

 No part of an organ which possesses motion and life 

 is destitute of nitrogen ; all of them contain likewise 

 carbon and the elements of water ; the latter, however, 

 in no case in the proportion to form water. 



The chief ingredients of the blood contain nearly 

 17 per cent, of nitrogen, and no part of an organ con- 

 tains less than 17 per cent, of nitrogen. (i)* 



The most convincing experiments and observations 

 have proved, that the animal body is absolutely incapa- 



* See Note XXVII. 



