136 



Scientific Proceedings (39). 



treppe represents increased irritability and increased working 

 power, due to the action of small quantities of carbon dioxide, 

 lactic acid and, possibly, other fatigue substances. 



If Frohlich's theory be correct, there should be a progressive in- 

 crease in the length of the successive muscle curves throughout the 

 treppe. This is found not to be so. When a muscle lever is made 

 to close an electric circuit automatically at the precise end of each 

 relaxation and thus to stimulate the muscle anew, it is found that 

 the length of the muscle curves at first increases and then decreases, 

 while the treppe is still proceeding. This fact does not seem expli- 

 cable by Frohlich's theory, but is what might be expected if the 

 treppe were due to the augmenting action of fatigue substances. 



Frohlich's theory demands that the irritability of the muscle 

 should progressively decrease from the time of the first contrac- 

 tion. This also is found not to be so. When the irritability of 

 the excised and non-curarized muscle, as indicated by the threshold 

 of stimulation, is determined at intervals throughout the course 

 of the treppe, it is found that the irritability progressively in- 

 creases. This again is in harmony with the theory of the treppe, 

 proposed by the senior author. 



85 (495) 



An attempt to discover the cause of the specific dynamic action 



of protein. 



By Graham ltjsk. 



[From the Physiological Laboratory of the Cornell University 

 Medical College at New York.] 



The writer has shown that if glutamic acid be given to a phlor- 

 hizined dog three of its carbon atoms are converted into glucose. 

 One can write the reaction thus: 



2HOOC • CH 2 • CH 2 • CHNH 2 • COOH + 2HOH = 



2CH3 COOH + C 6 H 12 0 6 +2NH 3 . 



Rubner sought to explain the increase in heat production which 

 followed meat ingestion — its specific dynamic action — by the sup- 

 position that protein could be used for the vital activities of the 

 cells only in so far as it was converted into dextrose; all the oxida- 

 tions of other portions of the protein yielded free heat within the 



