72 COLLOID CHEMISTRY OF THE PROTEINS 



A similar effect was noticed with acetic acid. Thus in Table 28 

 the quantity of combined acid in a half and a quarter of the 

 original albumin content is distinctly greater than a half and a 

 quarter of that found in the original concentration. This 

 result is due. to the suppression of hydrolysis by the relative 

 excess of acid in the lower concentrations of albumin (see 

 below). It does not represent, however, the maximum com- 

 bination, which takes place only in considerable excess of acid. 



Table 28. 



Acetic Acid + Ox-serum Albumin of 

 various Concentrations. 



On the other hand, in excess of acid, and when the maximum 

 combination has been attained, the quantity of combined acid 



0-01 



Actctec'. Acict 



0'5% 



O'OOt 



0-01 



FIG. 1 6. Glutin and hydrochloric acid. 



is proportional to the albumin content, and consequently this 

 value is specific for the protein concerned. Fig. 16, from the 



