THE PROBLEM AND METHODS OF INVESTIGATION 67 



and Loeb and Wasteneys have demonstrated that oxygen consump- 

 tion is greatly decreased in animals by cyanides, and it has also 

 been shown experimentally that the cyanides inhibit oxidations 

 and the action of oxidizing enzymes in various cases outside the 

 organism. To the hypothesis that the cyanides inhibit oxidations 

 in the organism the objection has been made that they affect, not 

 only aerobic or oxybiotic, but anaerobic animals as well, although 

 in the latter, oxidations requiring atmospheric oxygen do not occur. 

 In answer to this, it has been pointed out that even in anaerobic 

 forms oxidations occur, the oxygen being derived from substances 

 in the body instead of from the atmosphere. 



The cyanides and other substances containing the cyanogen 

 radical, CN, are in general extremely powerful poisons, but their 

 action resembles in certain respects that of the substances known 

 as narcotics or anesthetics. 



The characteristic physiological effect of all these substances is 

 a decrease or complete loss of irritability, which, however, is com- 

 pletely reversible up to a certain limit and so may be followed by 

 complete recovery. But the narcotics are like the cyanides poisons, 

 and if they act in sufficiently high concentration or for a sufficiently 

 long time they bring about changes of some sort which are not 

 reversible and which lead to death by retardation and final cessa- 

 tion of metabolism. Scientific investigation has thus far chiefly 

 concerned itself with the narcotic, i.e., the reversible, rather than 

 with the poisonous, irreversible, effects of these substances. Many 

 theories of narcosis 1 have been advanced, and most of them are 

 still in the field. Brief mention must be made of the more impor- 

 tant among these theories. 



Verworn and his school have long maintained that narcotics 

 decrease the oxidation processes and the respiratory activity of the 

 protoplasm, and Verworn has recently suggested that the narcotics, 

 either by adsorption or by loose chemical combination, render the 



1 The following references include some of the more important literature bearing 

 upon the different theories of narcosis: Alexander and Cserna, '13; Bernard, '75; 

 Dubois, '94; Hober, '10; Kisch, '13; R. S. Lillie, '120, '126, '130,, '136, '14; Loeb 

 and Wasteneys, '130,, '136; A. P. Mathews, '10, '13; H. Meyer, '99, '01; Overton, 

 '01; J. Traube, '040, '046, '08, '10, 'u, '13, etc.; Verworn, '03, '12, '13; Warburg, 

 'ioa, 'iob, 'ioc, 'na, 'nb, '120,, '126, '13, '140, '14^, '14^; Winterstein, '02, '05, '13, '14. 



