114 ANIMAL CHEMISTRY LECTURE V. 



with eight, nine, ten, and even sixteen atoms of carbon, the most 

 complex acids as yet obtained by the artificial oxidation of flesh, 

 are those with five, six, and seven atoms ; for the production of 

 toluic acid is at any rate very doubtful. Now, although this 

 oxidation of flesh has not been performed with sufficient fre- 

 quency, or variety of process, to warrant our laying much stress 

 upon the results obtained, still less of affirming that no more 

 complex aplone molecules than those with seven atoms of carbon 

 are in any case procurable, nevertheless the above observation, 

 taken in conjunction with other facts, has an interest which must 

 not be overlooked. Thus, among all the products of tissue-meta- 

 morphosis occurring in the living body, with the possible excep- 

 tion of indigo, which, like toluic acid, contains eight carbon 

 atoms ; among all the products of the putrefactive decomposition 

 of dead animal tissue ; among all the products obtainable by its 

 direct oxidation as just referred to ; and among all the products 

 obtainable by its indirect oxidation with acids or alkalies, not a 

 single aplone molecule with more than seven atoms of carbon has 

 yet been positively observed. 



(122.) Comparing the ascertained constitution of olein, for 

 instance, with the hypothetical constitution of some protein body, 

 we know that the molecule of olein contains 57 carbon atoms, 

 and that these atoms pertain to the residues of four distinct 

 aplone molecules, namely, three molecules of oleic acid, contain- 

 ing each 1 8 carbon-atoms, and one molecule of glycerin, con- 

 taining 3 carbon-atoms. Accordingly, by the breaking up of 

 olein we may obtain aplone molecules with as many as 18 

 atoms of carbon, and with successively fewer and fewer atoms, 

 according to the degree of oxidation, until finally we get such 

 bodies as succinic acid C 4 H6O 4 , oxalic acid C 2 H 2 O 4 , and carbonic 

 acid CH 2 3 ; while, among intermediate compounds, the palmitic 

 acid with 16, the sebacic and rutic acids with 10, and the suberic 

 acid with 8, are certainly, and other acids with from i to 18 

 carbon-atoms, in all probability, procurable. On the other hand, 

 the composition of the molecule of albumin is at present unde- 

 termined ; but assuming, according to the balance of authority, 



