216 Ohservations on the Rate of Action of Drugs, etc. 



The results in this respect were as follows : — 



Plate. 



Concentration. 



Temperature. 



Time. 



Temperature. 



Time. 







o 





o 



mins. 



634 



n 0 -0001 



1 



X 



18 



25 



681 



0-0005 



7 



oc 



19 



6-5 



682 



0 -0010 



7 



X 



19 



3-5 



We incidentally observed the course of recovery of muscles when the 

 experimental solution was replaced by normal saline. After alcohol, chloro- 

 form, and quinine, at the concentrations we used, recovery always took place 

 sooner or later ; but after aconitine, even at its lowest active concentration, 

 no recovery was ever observed. The recovery began sooner after intoxication 

 at low than at high temperatures, a result that we interpret as signifying that 



Aconitine, %/10000. The action of the drug is suspended at low temperatures. 



Fig. 16.- — October 28, 1909. Three groups of contractions with the muscle : 1, in normal 

 saline at 8° ; 2, in aconitine hydrochloride, 10000, at 8° ; 3, in normal saline at 17°. 

 During period 2, the aconitine diffused into the muscle ; during the period 3, 

 aconitine acted upon the muscle. 



Fig. 17. — Effect of aconitine hydrochloride, ?i/1000, at 19°. 



