176 Mr GRAHAM'S Account of the Formation of Akoates. 



over was of the specific gravity 0.800, at 60 ; the second mea- 

 sure, 0.798 ; and the third measure, 0.801 : the distillation was 

 then discontinued. These three measures were mixed together, 

 and subjected to a second distillation, which was conducted in 

 the same manner ; and two measures of alcohol obtained of the 

 specific gravity 0.796. It was found that farther rectification did 

 not reduce the specific weight of the alcohol below 0.796. From 

 the analysis of alcohol by SAUSSURE, and the determination of the 

 specific weight of its vapour by GAY LUSSAC, there can be little 

 doubt that the alcohol thus obtained is perfectly anhydrous. It 

 is true that such alcohol still contains oxygen and hydrogen to 

 the amount of an atomic proportion of water ; but this propor- 

 tion of oxygen and hydrogen is essential to the constitution of 

 alcohol, the partial abstraction of it converting alcohol into 

 ether, and its total abstraction converting alcohol into olefiant 

 gas ; while the supposition that the oxygen and hydrogen exist 

 in the state of water, is altogether gratuitous. 



The process of RICHTER is exceedingly tedious, from the ne- 

 cessity of conducting it so slowly, and the waste of alcohol is 

 considerable. I tried newly burnt quicklime instead of chloride 

 of calcium, and distilled by the heat of a saline water-bath. If 

 it is merely our object to obtain alcohol perfectly free from wa- 

 ter, no process could be more effectual. The product was of the 

 specific gravity 0.794 ; but it contained a trace of ether, to which 

 the extraordinary lowness of its specific gravity is attributable ; 

 and had an empyreumatic odour, notwithstanding the moderate 

 temperature at which the distillation was conducted. This like- 

 wise is a very slow process. 



The process which I preferred is founded on the principle of 

 Mr LESLIE'S frigorific apparatus. The alcohol is concentrated 

 by being placed under the receiver of an air-pump, with quick- 

 lime. A large shallow basin is covered to a small depth with 

 recently burnt lime in coarse powder, and a smaller basin con- 



