io8 



ACTIONS OF NARCOTICS 



oil-water partition coefficient which also determine nar- 

 cosis. 



The partition of a substance between oil and water can 



TABLE XX 



THE CONCENTRATIONS IN WATER OF VARIOUS SUB- 

 STANCES REQUIRED TO PRODUCE A GIVEN DEGREE OF 

 NARCOSIS IN TADPOLES, AND THE CORRESPONDING 

 EQUILIBRIUM CONCENTRATIONS OF THE SUBSTANCES 



IN OIL 



be regarded as determined by the sum of the differences 

 in free energy of its component groups in the two media. 

 From the data just given it is evident i . that there is a 

 parallel between equi-narcotic action and concentration 



