THE ACTIONS OF PHYSOSTIGMA AND ATROPIA. 603 



Several experiments, however, were made in which the administration of 

 the atropia was effected fifteen minutes after that of the physostigma. Their 

 results are as follows : — 



Experiment 273-a With 0*3 grain of sulphate of atropia, recovery occurred. 



Experiment 274-a. „ 0-5 „ „ > recovery 



Experiment 275-a. „ 1- „ „ recovery 



Experiment 276. „ 15 ,, ,, death „ 



Experiment 277. ,, 2* grains „ „ death „ 



With this interval, therefore, death is prevented from occurring by doses of 

 sulphate of atropia ranging from three tenths of a grain to one grain. It will 

 be observed that the range is a more limited one than that which was obtained 

 when the two substances were simultaneously administered, and also when the 

 interval was less than fifteen minutes. It is, however, very satisfactory to find, as 

 an indication of the remarkable efficacy of the antagonising influence of atropia, 

 that even when one and a half times the minimum-lethal dose of physostigma is 

 allowed to exert its toxic power without any interference for so long a period 

 as fifteen minutes, the administration of atropia is still able to prevent death. 

 The details of the experiments are of so great interest that I regret that it is 

 inadvisable to describe them fully, — since this could not be done without greatly 

 increasing the already formidable dimensions of this communication. I must 

 therefore content myself with referring to the abridged accounts contained in 

 the Tabular Summary. In all of the experiments, the animal was at the point 

 of death before the atropia was administered, and yet, in two or three minutes 

 threreafter, the gravity of the symptoms lessened with the most extraordinary 

 rapidity, not only in those experiments where perfect recovery was ultimately 

 effected, but even in those where the final result was death. On several 

 occasions also, an experiment that had been commenced could not be com- 

 pleted, because death occurred in less than fifteen minutes after the administra- 

 tion of physostigma, and, therefore, before the proper time had arrived for the 

 administration of atropia. 



When, indeed, the interval was greater than fifteen minutes, some difficulty 

 was experienced in obtaining any evidence whatever of the influence that is 

 exerted by atropia upon the toxic effect of this dose of physostigma. It was 

 only after several attempts, that I succeeded in performing the two following 

 experiments, in which atropia was administered seventeen minutes after one and 

 a half times the minimum-lethal close of physostigma. 



Experiment 278. — With 0*3 grain of sulphate of atropia, death occurred. 

 Experiment 279. „ 0*5 „ „ death „ 



In both experiments, death occurred : in the one, after the administration 



