ACIDS OF FLESH OXIDATION. 113 



hydrate constituents of muscle exist partly in combination with 

 an ammonia-residue derived from its nitrogenous constituents, 

 whereby, instead of the normal acids, we obtain, in some cases, 

 their dehydrated ammonia salts ; whence it follows that the ni- 

 triles, like the aldehydes, do not call for any separate considera- 

 tion, but may be discussed with their respective acids, of which 

 indeed, they constitute mere varieties. 



( 1 20.) The following acids, then, in the state of acids, aldehydes, 

 and nitriles, have been obtained by the oxidation of flesh with a 

 mixture of sulphuric acid and peroxide of manganese, as now 

 taking place in the retort upon the table : 



Fatty Acids Aromatic Acids 



Cg H I2 2 Caproic 



C 5 H J0 2 Valeric 



C 4 H 8 2 Butyric 



C 3 H 6 2 Propionic C 8 H 8 2 Toluic ? 



C 2 H 4 2 Acetic C 7 H 6 2 Benzoic 



C H 2 2 Formic C 6 H 4 3 Collie ? 



These several acids, you observe, contain but two atoms of 

 oxygen in their respective molecules, In reality, however, we 

 cannot doubt that corresponding acids with three and four atoms 

 of oxygen are also formed, as in other modes of oxidation ; but 

 such poly-oxygen acids being much less volatile than their di- 

 oxygen congeners, instead of being removed at once from the oxi- 

 dising mixture, remain in contact with it for so great a length of 

 time are subjected in fact to such a prolonged process of oxida- 

 tion that they become more or less completely destroyed, or, 

 in other words, converted into carbonic acid. 



( 1 2 1 .) Now, there are two special points of interest connected 

 with the above lists of muscle-acids, which are arranged, you 

 observe, in the order of simplicity, instead of complexity, as 

 heretofore. The first point to which I would direct your at- 

 tention is, that even the most complex of them is comprised 

 among the simpler members of its particular series. Thus, while 

 by the direct or indirect oxidation of fat we may obtain acids 



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