BY THE LIMITED APPLICATION OF HEAT. 279 



as the liquid ether. I have conjectured that this ether might be a compound 

 of the liquid ether with nitric oxide gas, or that it may be isomeric with the 

 liquid ether. Notwithstanding many efforts to obtain a liquid ether not re- 

 solvable partially into this gas, I have never succeeded. Hence the boiling 

 point is extremely variable, as I have seen bubbles escaping below forty de- 

 grees, from the liquid ether, when recently condensed after distillation. 



In the production of cold by mixture with solid carbonic acid, Dr. J. K. 

 Mitchell found this ether more efficacious than that commonly known as sul- 

 phuric ether, more properly called hydric ether. 



When the new ether, as it is first evolved, is distilled from powdered quick- 

 lime, this earth imbibes an essential oil, which, with the aid of water, is yielded 

 to pure hydric ether. Of course it is easy to remove this solvent by evapora- 

 tion or distillation. 



The odour of this oil seems to be an ingredient in that of ordinary nitric 

 ether. Possibly the hypo-nitrous ether may resolve itself gradually into this 

 oil and the gaseous ether; so that its boiling point may be probably varied by 

 this chemical change. I suspect that the essential oil in question is one of the 

 impurities which causes the boiling point of the ether generated by nitric acid 

 and alcohol to be higher than the boiling point of that obtained, as in my pro- 

 cess, by nascent hypo-nitrous acid. 



When the heat is raised, after the volatile ether ceases to come over from the 

 materials above mentioned as producing it, ethereal products are distilled, of 

 which the boiling point gradually rises as the process proceeds. Mean while, 

 the product thus obtained becomes more and more acrid, till at last it is ren- 

 dered insupportable to the tongue, as respects the after taste. On mingling 

 these liquids with a solution of green sulphate of iron, the ether is all absorbed ; 

 but an acrid liquid, which causes the after taste, is not absorbed, and may be 

 separated by hydric ether. The ether being vaporized by heat, the acrid li- 

 quid remains. The smallest drop of this liquid is productive of an effect upon 

 the organs of taste and smell like that of mustard or horse-radish. 



The new ether, when secured in a glass phial, by means of a well ground 

 stopper, does not undergo any change by keeping in a cool situation for several 

 months. A phial was suspended about fifteen feet below the surface of the 

 ground, in a cistern of water, for about five months; another was left in a cool 



