PHYSIOLOGICAL EFFECTS OF LACK OF OXYGEN * 371 



r~ 



produce carbon dioxide without containing oxygen that can 

 be exhausted by an air pump. 1 Pfluger 2 and Aubert 3 have 

 shown the same to be true for the living frog. No one 

 doubts that we are dealing with phenomena of splitting 

 in these cases, which are at the same time the source of 

 energy and the source for the motions, and the other physi- 

 ological functions that go on in the vacuum. The differences 

 observed by Spallanzani and Bunge in the length of time 

 that animals live without oxygen may therefore be explained 

 by assuming that different forms of animals contain different 

 amounts of hydrolyzable substances. As soon as this 

 material is used up "the clock stands still." Oxygen plays 

 the r6le of replacing the substances capable of undergoing 

 splitting which have been used up. 



By calculating the energy obtainable by the hydrolysis 

 and by the oxidation of carbohydrates Bunge has rendered 

 it probable that in the higher animals the production of 

 powerful work is not caused by hydrolysis alone, but by 

 hydrolysis and oxidation. According to this, lack of oxygen 

 could at once reduce the capacity for work of an animal by 

 limiting it to the energy which can be obtained from 

 hydrolysis. 



Hoppe-Seyler was the first to suggest a chemical theory 

 for the processes of oxidation which occur in the living organ- 

 ism. 4 He believes that, as in the process of putrefaction, 

 reducing substances (such as hydrogen in the nascent state) 

 are formed in all living cells through hydrolysis, and that 

 these substances, when atmospheric oxygen is present, tear 

 apart the oxygen molecule. The free oxygen atom is then 

 in the condition in which it is able -to bring about the oxida- 



1 Untersuchungen iiber den Stoffwechsel der Muskeln (Berlin, 1867). 



2 Pfliigers Archiv, Vol. X. 3 Ibid., Vol. XXVI. 



* At the time I wrote this paper I was not familiar with the papers of Traube on 

 the subject, which seem to give a more adequate presentation of the ti feet than 

 Hoppe-Seyler's hypothesis. [1903] 



