DISTILLATION. 259 



fire, that the alcoholic particles alone might be evaporated ; 

 a few moments of too great heat were sufficient to cause 

 the ascension of a great mass of aqueous vapor, by which 

 the alcohol was rendered deficient in strength ; the necessi- 

 ty of watching the fire, therefore, made the operation a very 

 difficult one. 



The union of so many faults in the apparatus, rendered it 

 impossible to extract the last portions of alcohol remaining 

 in the wine, without their being loaded with an immense 

 quantity of aqueous particles : this last product of distillation 

 was carefully separated under the name of small water ^ and 

 redistilled with a new portion of wine. 



The spirit obtained by the above process always has a 

 burnt taste, and is rarely very clear ; this arises from the 

 difficulty of regulating the fire, and the still greater difficul- 

 ty of obtaining, without increasing the heat too much, all 

 the alcoholic particles contained in the wine. 



If to the above-mentioned faults we add, that the furnaces 

 of these alembics were badly constructed, that they present- 

 ed no means either of regulating the heat, or of applying it 

 equally to the whole body of the liquor, we shall see that the 

 art of distilling was yet in its infancy. 



I was aware of these defects, and attempted to correct 

 them, and in consequence I caused to be made large boilers 

 of but little depth, that as great a surface as possible might 

 be presented to the fire ; I surrounded the cap with a bath of 

 cold water ; this produced the first condensation, and separa- 

 ted the aqueous particles, which fell back in drops or streams 

 into the boiler ; I increased the number of windings in the 

 worm, and enlarged the bath-cask, that the water might not 

 so soon become heated. These alterations were approved of, 

 and distillation was established upon these principles. My 

 apparatus and that of M. Argand, who had wonderfully ini- 

 proved the furnace, was employed with success during fifteen 

 or twenty years. 



In the first years of the present century, the art of distilla- 

 tion was established upon new principles, and it has gone far 

 beyond all that was before known and practised. A chymi- 

 •cal apparatus, by means of which vapors or gases were made 

 to pass through liquids which were to be saturated with them, 

 gave to Edward Adam the first idea of his apparatus for dis- 

 tillation ; a knowledge of the fact that aqueous vapors are 

 condensed at a degree of heat which does not effect a like 

 change in alcoholic vapor, fiirnished him with the means of 

 completing his apparatus. 



