180 PROTOPLASM 



Furthermore, the retardation of inanimate oxidation by narcotics 

 rises with the adsorption constants of the narcotics used (methyl, 

 ethyl, propyl, and phenyl urethane). Apparently, the oxida- 

 tion of oxalic acid into carbon dioxide and water in the presence 

 of charcoal takes place on the surface of the charcoal, from which 

 it may be assumed that the oxidation of sugars into carbon 

 dioxide and water in cells {i.e., respiration), takes place on the 

 surface of infinitely small protoplasmic particles. Any diminu- 

 tion of these surfaces will mean a decrease in oxidation. Nar- 

 cotics are readily adsorbed by charcoal and by blood particles 

 and thus decrease the surface available for oxidation. (The 

 blood particles that Warburg has in mind are ultramicroscopic 

 ones.) Narcosis and anesthesia are thus regarded as a retarda- 

 tion of oxidation due to decrease in the free adsorptive surface 

 of blood particles through adsorption of the narcotic The 

 hypothesis is a feasible one and has other facts to support it; 

 thus, the members of the following homologous series of alcohols 

 are adsorbed in increasing amounts as we ascend the series, and 

 the narcotic effects also increase in this wise. 



Concentrations 

 Required to Cause 

 Anesthesia of 

 Alcohols Tadpoles, M 



Methyl . 60 



Ethyl 0.30 



Propyl 0.10 



A^-butyl 0.04 



The evidence supporting Warburg's hypothesis is offset by 

 the fact that methanes and hydrocarbons show little or no surface 

 activity, yet all are good anesthetics. Surface activity or 

 adsorption rests in large measure on the polarity of the molecules 

 involved (page 256) ; hydrocarbons are nonpolar and therefore 

 not adsorbed, but they are strong narcotics. Furthermore, 

 many substances, such as the sugars, are readily adsorbed and 

 have no narcotic effect whatever. And, finally, the cyanides, as 

 narcotics, are ten thousand times more effective than they ought 

 to be if they must cover a suflficient surface. The cyanides may 



