STUDY OF MOLECULAR ADHESION. 437 



by eel serum and by alexin, however, does not occur under these 

 conditions. We may leave aside hemolysis by alexin, inasmuch 

 as it is known to be very much altered by dilution in a medium 

 which is poor in salts. The failure of hemolysis by eel serum in 

 a sugar medium is not, however, due to an alteration in the 

 hemolysins, but to deprivation of salts. When we dialyze eel 

 serum against distilled water we find the globulins which are pre- 

 cipitated by this treatment contain no hemolysin, but that this 

 substance remains intact in the limpid portion of the dialyzed 

 serum. We have found, moreover, that the reason this hemolysin 

 does not dissolve red blood cells in a sugar medium is due to the 

 fact that under such conditions it is not adsorbed by the cells. 

 The addition of salt to such a mixture, however, brings about 

 adhesion of the hemolysin to the cells, and their dissolution. 

 When we compare the activating power of various salts, we 

 find that they depend on the kation and that the salts of the 

 alkali earths are much more potent than corresponding salts 

 of alkali metals; the activating strength of the salts increases, 

 then, parallel to their flocculating action on unstable negative 

 colloids. 



In this case, also, it would seem that the electrolytes increase the 

 adhesive property of the particles of the hemolysin in eel serum for 

 corpuscles by increasing their superficial tension in the same way 

 that they increase the adhesive power of the particles of an unsta- 

 ble negative colloid for one another.* This evidently does not ex- 

 plain the action of the salts; we may, however, say that such 

 salts increase the adhesive power of a suspended substance for other 

 suspended substances as if they increased the affinity of the particles 

 of such a suspended substance for similar particles. It would seem 

 to us as difficult to explain the adsorption on the addition of salts, 

 of substance A by substance B — and particularly of the hemolysin 

 of eel serum by red blood cells — as a purely chemical phenomenon, 

 as it is to explain the reciprocal adhesion between particles of a 



* This phenomenon may be compared with the facts that have been mentioned 

 by Nasse (Pfliig. Archiv. fur Physiol., 1885, Vol. 37) and by Bayliss (Biochem. 

 Journal, I). Nasse found that the adsorption of iodine by glycogen is increased 

 by salts; Bayliss demonstrated that the coloring power of electronegative colloidal 

 dyes for paper is increased by the kations and inhibited by the anions, and that 

 the inverse is true with electropositive colloidal dyes 



