196 PROTOPLASMIC ACTION AND N'ERVOUS ACTION 



concentrated in the cells as in the medium. Formal- 

 dehyde and HCN also underwent concentration in the 

 cells. The series, methyl alcohol < butyl alcohol <amyl 

 alcohol < phenyl -methyl ketone < phenyl ure thane < 

 thymol represents the order both of increasing physio- 

 logical action and of increasing concentration in the 

 cells. 



On the whole the foregoing studies of the distribution 

 of narcotics between cell and medium appear to favor the 

 partition theory of the action of these compounds. It 

 should be pointed out, however, that the order of relative 

 adsorption is in general the same as that of hpoid- 

 solubility . The probabiUty, as already pointed out, is that 

 both solution and adsorption are factors in the total effect. 



CORRELATION BETWEEN PHYSIOLOGICAL ACTION 

 AND SURFACE -ACTIVITY 



The relation between the narcotic or other physio- 

 logical action of organic compounds and their influence 

 on surface-conditions has recently received much investi- 

 gation. The majority of compounds of the lipoid- 

 alterant group have a marked influence in lowering the 

 surface-tension at the boundary-surfaces between their 

 aqueous solutions and air or other adjoining phase; 

 at the same time, in accordance with the Gibbs-Thomson 

 rule, they undergo increase of concentration (or adsorp- 

 tion) at such surfaces. In homologous series both the 

 influence on surface-tension and the degree of adsorption 

 increase progressively with increase in molecular weight; 

 and the view that the physiological action is determined 

 by this surface-action, i.e., by the condensation of the 

 compounds at the protoplasmic phase-boundaries, rather 



