54 KEPORT — 1867. 



Nitrite and Nitrate of Methyl. 



The nitrite and tlie nitrate of methyl possess an action so much in com- 

 mon that I may take them together. The nitrite made by the action of ni- 

 trous acid on methylic alcohol is most conveniently used with ether. The 

 nitrate made by distilling the wood-spirit with nitrate of potash and suljihuric 

 acid can be used directly. It is a heavy liquid, having a specific gravity of 

 1-180 and a boiling-point of 140° Fahr. 



As with the nitrites of amyl and ethyl, the action of these substances is 

 to produce intense excitement and rapid action of the heart and arteries. 

 The action, however, is not so vehement as from nitrite of amyl, and a lon- 

 ger inhalation is required before the excitement is perceived. In the human 

 subject the face becomes red, the vessels of the head seem fall and distended, 

 and the pulse is readily brought up to 120 and even 130. On the inferior 

 animals the same excitement is manifested, and death is preceded by convul- 

 sive jerks. After death the lungs are found collapsed and v.liite, and the 

 heart flaccid and full of blood on both sides. On exposure to the air the 

 heart recommences to contract, and continues its contractions for long periods, 

 in one case (a rabbit being the subject) for forty minutes. The blood in the 

 blood-vessels remains fluid for an hour or more, but coagulates readily on 

 exposure to a Avarm air. The muscles througliout the whole of the body are 

 flaccid, but will contract, for periods of one and two hours after death, under 

 the influence of the galvanic current. Neither nitrite nor nitrate of methyl 

 produce true ana3sthcsia. 



Of the two substances the nitrate of methyl is most conveniently used, 

 and as it possesses aU the physiological properties of nitrite of amyl with less 

 energy, it would, I tliink, be the best agent in medicine. Its power in pro- 

 ducing muscular relaxation is most marked and general, and its employmcjit 

 in cases of a desperate spasmodic character, as in tetanus, would be a ratioiial 

 scientific procedure. 



I now come to the second group of substances to which I have directed 

 attention; viz., cliloroform, tetrachloride of carbon, and bichloride of metliy- 

 lene. 



Chloroform. 



Chloroform made by the action of bleaching-powder on methylic alcohol, 

 or ethylic alcohol, is a substance so well known as an anaesthetic that I shall 

 dwell but very briefly upon it. It has a specific gravity of 149.5, and it boils 

 at 142° Eahr. From the large number of experiments I have made v.'ith this 

 substance to determine its mode of action, and the manner in which it some- 

 times destroys life, I am led to the conclusion that its fii-st influence is always 

 exerted on the centres of motion of the nervous system with an extension of 

 that action to the centres of volition and sensation. I agree with Dr. Snow 

 in tracing out four distinct stages in its action, one of gentle excitement of 

 the circulation, a second of exalted action of the motor centres, a tliird of 

 depression of motion with destruction of consciousness, and a fourth of com- 

 plete paralysis of motion and sensation. I have also been led slowly to the 

 conviction that the cause of death from chloroform is in every case due to 

 arrest of nervous function, and that the idea of any direct action of tlic agent 

 on the muscular structure of the heart is without foundation. In eighty-seven 

 experiments conducted specially to determine the direct influence of chloro- 

 form on the heart, I found in every case that organ capable of reaction on its 



