412 iiEPOKT— 18G9. 



the heart are left full of blood, are natural in colour ; thej- are not blanched, 

 as after chloroform, nor congested, as after ether. The brain is natural. 

 The muscular irritability is long retained. 



To put the hydride to further test, I inhaled the vapour of it myself from a 

 Vulcanite inhaler, such as I employ for bichloride of methylene : the vapour 

 was very agreeable to breathe, caused no cough and no irritation, but a sen- 

 sation as of a gentle warmth or glow in the chest. After six inspirations I felt 

 evidences of change in the cerebral circulation, giddiness, and inability to 

 stand, with the common swaying movement, or sense of movement, which 

 marks the first degree of anaesthetic sleep. In a little time T lost conscious- 

 ness for a few moments ; but the inhaler being removed I quickly recovered, 

 and in three minutes was perfectly well. Neither nausea, nor headache, nor 

 chilliness followed. 



Owing to the low boiUug-point of this hydride, it admits of being employed 

 by the physiologist for many inquiries bearing on the restoration of animal 

 life after some forms of death. Thus, after destroying in frogs, by the action 

 of extreme cold, those functions or acts which constitute what is called life, 

 the process of recovery is best determined by regulating the slow restoration 

 or return of heat, and by preventing a suddenness of reaction which ordinarily 

 is fatal. Now, by immersiijg the animal in the hydride of amyl, and then 

 warming, there is no danger of warming too quickly, as the fluid boils at 86° 

 Fahr. ; neither is there any necessity for removing the animal until, by the 

 escape of a bubble of gas from the mouth, the first indications of restoring 

 respiration are afforded ; then the animal removed will, in most cases, re- 

 cover in the op3n air. I have seen the frog recover after immersion under 

 this hydride for a period of seven minutes. 



Ou the whole, I am of opinion that pure hydride of amyl might, if it were 

 needed, be employed as a general anaesthetic, and that, for short operations 

 especially, it would be effective. I do not, however, put it above the other 

 anaesthetics, but would rather assign to it the same position as belongs to 

 ethylic ether, amylene, and nitrous oxide gas. 



I must not, however, pass over some other minor but, in the aggregate, 

 important uses of this agent. At a very moderate cost now, a hydride may 

 be obtained which, though not absolutely answering to its pure chemical 

 character, is sufficiently pure for the purposes I shall name, and which must, 

 when the value of it is made known, ensure, I think, its employment by all 

 practitioners of the healing art. I will notice some of its applications in 

 detail, but by no means all of them. 



From the fact that tlie hydride boUs at a temperature twelve degrees below . 

 the natural temperature of the human body, it is very useful as a fluid for 

 producing, in form of spray, rapid local insensibility. In most persons it 

 produces insensibility, in this manner, in a period of from one to two 

 seconds, and for mere punctures or slight incisions it answers well ; but for 

 larger essays it is too volatile, and does not cover a sufficient surface. It is 

 advisable, therefore, to dilute it with absolute ether, by which means the 

 best compound that can be employed for producing rapid local insensibility is 

 secured. 



The hydride of amyl dissolves some juices and fats with great facility. 

 Camphor and spermaceti dissolve in it freely, and the vegetable and animal 

 oils mix wth it. Advantage may be taken of these properties for making a 

 solution I have placed before the Section, and which is most valuable for re- 

 lieving the pain of burns. The solution is made by saturating the hydride 

 with spermaceti, then adding camphor until that ceases to dissolve, and finally 



