1909.] Observations on the Rate of Action of Drugs, etc. 213 



The observed and calculated times compare as follows : — 



Times (obs.). Times (calc). 



24-5 24-5 



21 21 



13 13-5 



10- 5 10-5 



11- 0 10-5 



The error is +0-5 minute. 



Quinine Hydrochloride. 



We took quinine hydrochloride as a typical and familiar drug readily 

 obtainable in reasonable purity, and with the action of which upon muscle 

 we had become well acquainted in course of comparative observations on the 

 cinchona alkaloids.* The results were as follows : — 



Temperature. 



Times. 



Log T,/T„. 



Log Lo/Li. 



m. 



o 



mins. 









7 



53 



0 -0000 



0 -0000 





12 



35 



0 -0076 



0 -1802 



26 



18 



22 



0 -0167 



0 -.3818 



22 -8 



19 



16 



0 -0182 



0 -5201 



28 -5 



19 



15-5 



0 -0182 



0 -5339 



28 -8 



20 



15 



0 -0197 



0 -5481 



28 -3 



25 



10 -5 



0 -0270 



0 -7030 



26 -0 









Mean 



26 -7 



The graph of these results is as under. From the mean value of m = 267 

 the coefficient of increase for 10° is 2'52, a number which is not widely 

 different from that found (viz., 2'44) for the reaction between chloric acid 

 xind ferrous sulphate.f 



* 'Physiol. Soc. Proc.,' Oct., 1909. 



t Hood, 'Phil. Mag.,' 1885, [5], vol. 24. 



