260 CHYMISTRY APPLIED TO AGRICULTURE. 



The chymical apparatus suggested to Adam the idea of 

 conducting, by the aid of a copper tube, the vapor which 

 rises from a boiler of wine placed over the fire of a fur- 

 nace, into a second boiler of the same liquid, which is 

 thus heated to the boiling point : the vapor from this second 

 boiler may be carried into a third, in which ebullition will 

 likewise take place ; and thus by means of a fire kept under 

 one boiler, distillation may be carried on in two or three, 

 provided they are well closed. This mode of transmitting 

 heat is now practised in most foreign distilleries, and it is 

 called heating hy steam. 



Edward Adam, by the process just detailed, made a 

 great saving of fuel, and was sure that the spirit obtained 

 would always be free from a burnt taste. He also saved 

 time and labor, for the workman whose business it was to 

 attend one furnace, accomplished much greater results, 

 than if that fire caused the evaporation of but one boiler. 

 These were certainly great improvements, but it was 

 necessary to go still further, and to find the means of ob- 

 taining alcohol in its greatest possible purity by freeing it 

 from all aqueous particles, and this he did by applying to 

 his apparatus the second principle which we have already 

 specified. " By making," he says, " the alcoholic vapor 

 which rises out of the last boiler pass into vessels im- 

 mersed in a bath of cold water, the aqueous vapor will be 

 condensed, and I can then bring it back again into the 

 first boiler, to be there redistilled, whilst the alcoholic va- 

 por will pass out of these vessels, without being con- 

 densed, into the worm, where it will undergo condensa- 

 tion." 



Proceeding upon this reasoning, founded upon positive 

 facts, he adapted a tube to the upper part of the last boiler ; 

 this tube conducts the vapor into a first condenser, which is 

 of a spherical form and immersed in a water bath ; in this, 

 a part of the aqueous vapors are resolved into a liquid form, 

 and this liquid is carried by a pipe into the wine of the first 

 boiler, to be redistilled and deprived of the small portion of 

 alcohol which it still holds in solution ; the vapors which 

 cannot be condensed in the first receiver pass into a second, 

 where a new condensation takes place in consequence of 

 the temperature being less elevated; from the second it 

 goes into a third, and thence into a fourth ; that which is 

 condensed returns, as I have just said, into the boiler, where, 

 by a new distillation, it is deprived of all its remaining spir- 

 ituous portions. 



