174 DRS CRUM BROWN AND FRASER ON THE CONNECTION BETWEEN 



all spasmodic, was the last symptom to disappear, which it did about two hours 

 and thirty minutes after the injection of the poison. We frequently tested the 

 condition of the reflex activity, and did not find it increased at any period 

 during the experiment. 



Experiment LXXVIII. — Five grains of sulphate of methyl-thebaium was dis- 

 solved in thirty minims of distilled water, and injected under the skin of a rabbit, 

 weighing four pounds and half an ounce. Its effects began to be seen in thirteen 

 minutes, when, after a few restless movements, the rabbit subsided on the abdo- 

 men and chest. Complete flaccidity soon after occurred ; and the respirations be- 

 came shallow and gasping, and they diminished in frequency until, at twenty-five 

 minutes after the injection, they were only at the rate of twenty-three per minute. 

 Occasional, very weak, tremulous movements occurred at this time. In thirty-five 

 minutes, severe pinching of the skin caused only a feeble reflex movement, while 

 the contraction of the eyelids, after irritation of the eyeball, was almost imper- 

 ceptible. The rabbit appeared still to retain consciousness. In fifty minutes, no 

 movement followed severe pinching of the skin, or irritation of the eyeball, and 

 the respirations were gasping and infrequent. In fifty minutes, a few twitches 

 occurred in the muscles of the face, and either immediately before or during 

 these the rabbit expired. 



In the autopsy, which was immediately performed, the heart was seen con- 

 tracting at the rate of seventy-eight per minute, and the intestinal peristalsis 

 seemed normal. Four and a-half minutes after death, neither a weak nor a 

 powerful galvanic current could excite any muscular contraction when applied 

 to the trunk of a sciatic nerve ; but idio-muscular irritability was not lost for 

 many minutes after this. At two hours and thirty minutes after death, the rabbit 

 was still perfectly flaccid, and there was not the slightest appearance of muscular 

 rigidity. 



We have not observed any symptoms follow the internal administration of 

 this substance, as no effect was produced when we introduced twenty grains, dis- 

 solved in warm water, into the stomach of a rabbit. It has been shown by Experi- 

 ment LXXIV. that four grains of thebaia is a fatal dose when thus exhibited. 



The experiments we have narrated contain the most satisfactory proof that the 

 chemical addition of iodide and sulphate of methyl has produced a complete 

 change in the physiological action of thebaia. The nature of the change appears 

 to be identical with that we have described as occurring under similar circum- 

 stances in strychnia and brucia. Thebaia acts in the same way as these alkaloids ; 

 for it causes increase of the reflex activity, convulsions, and tetanus by an action 

 on the spinal cord. The action of iodide and sulphate of methyl-thebaium is strik- 

 ingly different ; for they diminish reflex excitability, and produce a condition of 

 paralysis in which death occurs by asphyxia. This paralysis, as we have seen, is 

 dependent on an effect on the spinal nerve system. 



