1910. | with the State of Aggregation of Matter. 99 
NH, OH Be coe ——— 
Gl)S i (Gl) #0 + (Gi) » NGGiy. 
\coon * NHOH/ \cooH non 
i.e. neutralisation can take place between the acid group of one globulin 
molecule and the basic group of another. If either the acid or basic 
functions, or both, be sufficiently well marked, the product formed by the 
combination of two molecules will be stable, and will undergo but little 
hydrolysis in the presence of water (7.c. the reaction in the above equation 
will proceed nearly to completion in the direction indicated by the arrow 
pointing to the right). The nature of the globulins can be explained by 
assuming that the undissolved globulin is a complex of this type, which in 
the presence of water undergoes but little hydrolytic dissociation. That 
a certain amount of hydrolysis does take place, however, is indicated by 
Hardy’s observation that after repeated washing of serum globulin by water, 
the washings have always a higher electrical conductivity than the wash 
water. If salts be added to the water and adsorption on the surface of the 
dissociated globulin takes place so that it is stereochemically inhibited by 
the adsorbed salt molecules from forming aggregates by salt formation with 
other molecules, then the equilibrium between the solid undissociated 
globulin and water will be disturbed; the more rapidly the salt molecules 
are adsorbed, the further will reaction proceed in the direction of the arrow 
pointing to the left in the above equation, and the more the globulin will 
appear to be dissolved (or to speak perhaps more correctly, to be disaggre- 
gated). In offering this explanation as to the nature of the globulins one 
assumption has been made, viz. that in aggregation under “chemical 
stimulus ” (ze. salt formation) the molecule reaches such large dimensions 
that it is no longer capable of forming even colloidal solutions, but becomes 
insoluble. This assumption is supported, however, by certain experimental 
facts demonstrated by Hardy in the case of serum globulin and by Osborne 
in the case of edestin.* In their determinations of the solubility of globulins 
in acids and bases, it was found that the same solvent capacity was possessed 
by equimolar and not by normal solutions (7.e. HCl = H2SO, = H3PO,: 
NaOH = Ba(OH)2). This fact can be explained by assuming that in the 
case of the polybasic acids only the acid salts of the type (er) 0, 
are soluble, and the neutral salts of the type (er) 0 are insoluble ; 
similarly, salts of the type (av) are also insoluble. In both these 
* Loc. cit. 
