36 ANIMAL CHEMISTRY LECTURE II. 



Lastly, we have the carbonic and oxalic series of acids apper- 

 taining to the primary monobasic acids, and to the above tabulated 

 alcohols and aldehydes : 



Diatomic Fatty Acid Series 



C H a 3 Carbonic 



C a H 4 3 Glycolic C a H a 4 Oxalic 



C 3 H 6 3 Lactic C 3 H 4 4 Malonic 



C 4 H 8 3 Bulatic C 4 H 6 4 Succinic 



C 5 H I0 3 Phocic C 5 H 8 4 Pyrotartric; 



C 6 H la 3 Leucic C 6 H I0 4 Adipic 



C 7 H I4 3 ^j C 7 H IZ 4 Pimelic 



C 8 H I6 3 I C 8 H I4 4 Suberic 



C 9 H I8 3 [ Banting C 9 H l6 4 Anchoic 



C IO H, 3 J C IO H I8 4 Sebacic 



Accordingly, when we break up any complex animal product 

 into its simpler constituent molecules, by an absorption of water, 

 we are always, or nearly always, able to refer each of the com- 

 pleted molecules to its appropriate position in some homologous 

 series and in some heterologous grouping ; just as we accord to 

 common ethylic alcohol its proper place both in the series of 

 alcohols and in the group of acetic compounds. 



(35.) Now, let us apply these several considerations to unravel 

 the composition and relationship of some particular animal pro- 

 duct, say hippuric acid, of which a very beautiful specimen, 

 kindly lent me for the occasion by Messrs. Hopkins and Williams, 

 stands on the table before you. This acid is represented by the 

 very complex formula C g HgNO 3 , and is composed, therefore, of 

 22 constituent atoms. It is now known to consist of a residue of 

 benzoic acid, a residue of oxiacetic or gly colic acid, and a residue 

 of ammonia, united with one another in a particular manner. 

 The positions of the benzoic and gly colic acids in the groups 

 and series' to which they belong have been already referred to 

 the benzoic being the second term of the primary aromatic 

 acid series, and the glycolic the second term of the carbonic 

 acid series the former being the pivot of the benzoic, the latter 

 a well known member of the acetic group. 



