288 ANNUAL OF SCIENTIFIC DISCOVERT. 



gions of the head in which the elevation of temperature was most 

 marked, it was generally found that the best results were obtained 

 just above the occipital protuberance. This statement applies to 

 all the experiments that have been related. In the last-mentioned 

 series of observations it was not unfrequently found that the tem- 

 perature of the forehead fell, while that of the back of the head 

 rose ; but for what reason I have not yet been able to determine. 

 — New York Medical Journal. 



BELATION OF THE CHEMICAL CONSTITUTION AND PHYSIOLOGICAL 



ACTION OF MEDICINE. 



At one of the recent meetings of the Royal Society of Edin- 

 burgh, a very interesting paper was read by Drs. Crum Brown 

 and T. R. Fraser, upon the influence of direct chemical addition 

 upon the physiological action of substances. 



In order to arrive at any accurate knowledge as to the influence 

 which chemical constitution exerts upon physiological action, it 

 would appear to be desirable to take substances having a very 

 definite and energetic physiological action, and then to perform 

 upon them a chemical operation having for its object the promo- 

 tion of a definite change in the constitution, and to examine the 

 modification which the physiological action has undergone. Such 

 has been the plan the authors have pursued. The bodies which 

 they have chosen for examination are the more active of the vege- 

 table alkaloids, and the chemical operation, of which they have 

 studied the effect, has been the direct addition of iodide of 

 methyl. It was shown by How that, when iodide of methyl acts 

 upon strychnia, brucia, morphia, and other alkaloids, it adds itself 

 to them, and beautiful crystalline bodies are produced which differ 

 considerably in character from the salts of the alkaloids. 



It is well known that doses of strychnia, varying from one- 

 twentieth to one-thirtieth of a grain, rapidly produce in rabbits 

 most violent convulsions, and in a few minutes kill the animal ; 

 the phenomena produced being a localization of its action on the 

 cord. It was found that 12 grains of iodide of methyl-strychnium, 

 when administered (by subcutaneous injection) to rabbits weigh- 

 ing 3 pounds, produced no effect whatever. Fifteen grains pro- 

 duced symptoms, and 20 killed ; but the animal died with symp- 

 toms altogether different from those produced by strychnia. In 

 place of violent and spasmodic convulsions and muscular rigidity, 

 the appearances were those of paralysis with complete general 

 flaccidity. The spinal motor nerves were either paralyzed, or 

 speedily became so ; and, instead of the speedy occurrence of 

 muscular rigidity, the muscles remained flaccid, contractile, and 

 alkaline for several hours. In short, by the addition of iodide of 

 methyl to strychnia, the toxic properties of the latter are dimin- 

 ished about 140 times ; and the body produced possesses the 

 physiological action of curare ; namely, paralysis of the end- 

 organs of the motor nerves. 



Similarly, Brown and Fraser have discovered that the toxic 



