CHEMICAL CONSTITUTION AND PHYSIOLOGICAL ACTION. 



181 



Experiment XCIX. — In a frog, weighing 694 grains, the left gastrocnemius 

 muscle was prepared in the manner described in Experiments XXIX., LVIL, 

 and LXXX., and one grain of sulphate of methyl- codeium, dissolved in distilled 

 water, was injected into the abdomen by means of a Wood's syringe. In one 

 hour after this, a condition of flaccidity being present, the trunks of the two sciatic 

 nerves were exposed, and stimulated with an interrupted galvanic current. When 

 the right nerve was thus treated, some contractions followed in the left leg, and 

 nowhere else ; and when the left nerve was thus treated, vigorous contractions 

 followed in the left leg ; and it was observed that the movements of the left leg 

 were caused by contractions restricted to its gastrocnemius muscle, that is, the 

 muscle to which the poison had no direct access. At this time, the muscles in 

 all parts of the body contracted freely when the poles of the battery were applied 

 to their surfaces, and continued to do so for many hours longer. 



We repeated these last experiments with iodide of methyl-codeium, and 

 obtained the same general results. 



We have, therefore, demonstrated that iodide and sulphate of methyl-codeium 

 produce paralysis, by destroying the function of the peripheral terminations (end- 

 organs) of the motor nerves — a mode of action that distinguishes them, as 

 physiological agents, in a most striking manner from codeia. It will also be seen 

 from the following table, that the poisonous (toxic) activity of the codeia in these 

 methyl-compounds is considerably diminished. 



No. of 



Substance 



Animal and its 



Method of 



Dose. 



Effect. 



Experiment. 



employed. 



weight. 



exhibition. 







LXXXIV. 



Iodide of methyl- 



Rabbit, 2 lbs. 14 oz. 



Subcutaneously. 



15 grs. (contain- 



Paralysis in 25 minutes. 





codeium. 







ing 10 - 2 grs. of 

 dry codeia). 



continuing for about 3 

 hours, and followed by 

 recovery. 



LXXXIX. 



Codeia (crystal- 



Do. (same rabbit as 



Subcutaneously. 



1 gr. (contain- 



Spontaneous twitches in 





lised). 



in Ex. LXXXIV.) 





ing 0-94 gr. 

 of dry codeia). 



15 minutes, tetanus in 

 1 hour and 11 minutes, 

 and death in 1 hour and 

 45 minutes. 



XCI. 



Iodide of methyl- 

 codeium. 



Do., 2 lbs. 13 oz. 



By stomach. 



30 grs. (contain- 

 ing 20'3 grs. of 

 dry codeia). 



No effect. 



XCIV. 



Codeia (crystal- 



Do. (same rabbit as 



By stomach. 



10 grs. (contain- 



Sleepiness in 24 minutes, 





lised). 



in Ex. XCI.) 





ing 9 '4 grs. of 

 dry codeia). 



increase of reflex exci- 

 tability in 39 minutes, 

 and followed by recovery 

 in more than 3 hours. 



XCVI. 



Sulphate of me- 



Do., 4 lbs. 



Subcutaneously. 



8 grs. (contain- 



Paralysis in 33 minutes, 





thyl-codeium. 







ing 66 grs. of 

 dry codeia). 



continuing for more than 

 20 minutes, and followed 

 by recovery. 



c. 



Sulphate of me- 

 thyl-codeium. 



Do., 4 lbs. 13 oz. 



By stomach. 



20 grs. (contain- 

 ing 16'5 grs. of 



No effect. 











dry codeia). 





