Effect of Certain Organic Acids and Amino Compounds. 57 



a swelling less than that in distilled water, a result that suggests a 

 rapid solution or dispersion from the surfaces of the sections and alter- 

 ations of viscosity in the mass. 



Table 45. — Hydration of agar, gelatine, agar-gelatine, and agar-oat protein in organic acids 

 and their amina-compounds at 16° to 17° C. Expansion in percentages of dried thickness. 



Mixtures of agar (8 parts) and gelatine (2 parts) were now tested, 

 and the hydration in succinic acid at 0.00008 M was but 1,030 per 

 cent, as compared with 1,684 per cent in water, while acetic acid was 

 slightly higher, 1,167 per cent. A similar statement would hold for 

 the action of these acids on agar and for agar-protein, the hydration 

 in water alone being reached more nearly than in the agar-gelatine 

 sections. 



When we now turn to amino-succinic or aspartic acid and amino- 

 acetic acid or glycocoU, some new relations are uncovered. The 

 aspartic acid appeared to exercise a notable influence on the hydration 

 of agar. The limit of its solubility appeared to be about 0.05 M 

 at 15° to 20° C. When more than this was added to the water 



