RESEARCHES ON CHLOROFORM ANAESTHESIA 651 



content of the blood quickly approximates to a maximal value, 

 which is maintained until asphyxial convulsions occur. This 

 may be termed the second danger period. The difference 

 between the chloroform-content of the blood at the initial 

 period, when the first danger point is reached, and also at the 

 maximal value, when compared with the lethal amount, is very 

 minute. The quantity of the drug in the blood governs the 

 distribution of the anaesthetic which at first stimulates, and 

 then finally paralyses certain cell districts of the body in 

 definite order. Chloroform, therefore, though a toxic substance, 

 does not produce its eff'ects upon the organism by a cumulative 

 action ; these are not dependent upon the absolute quantity 

 which is supplied, but upon the percentage-value of the drug 

 in the blood stream. 



