442 Experiments to ascertain the Slate of 



The proofs which have been brought forward in support 

 of this theory, are chiefiy founded on the researches of Fa- 

 broiii*, who attempted to separate alcohol by saturating 

 the wine with dry subcarbonate of potash, but did not suc- 

 ceed, although bv the same means he could detect very mi- 

 nute portions of alcohol which had been purjioselv added. 



To obtain satisfactory results from many of the following 

 experiments, it became necessary to employ \\ ines to which 

 little or no spirit had been added ; for a very considerable 

 addition of brandy is made to most of the common wines, 

 even before tliey are imported into this country. I there- 

 fore occasionally used Burgundy, Hermitage, Cote Roti, 

 Champagne, Frontignac, and some other French wines, to 

 which, when of the best quality, no spirit can be added, as 

 even the smallest proportion impairs the delicacy of their 

 flavour, and is consequently readily detected by those who 

 are accustomed to taste them. For these, and for ihe op- 

 portunity of examining many of the scarce wines enume- 

 rated in the table annexed to this paper, I am indebted to 

 the liberality of the Right Hon. Sir Joseph Banks. 



Dr. Baillie, who took considerable interest in this inves- 

 tigation, was also kind enough to procure for me some Port 

 wine, sent from Portugal for the express purpose of ascer- 

 lainins how long it would remain sound, without any ad- 

 dition whatever of spirit having been made to it. 



Lastly, 1 emploved raisin wine which had been fermented 

 without the addition of spirit. 



At a very early period of the present inquirv, I ascertained 

 by the following experiments, thai the separation of the 

 alcohol by means of subcavbonalc of potash was interfered 

 with, and often wholly prevented, by some of the other in- 

 gredients of the wine. 



A pint of Port wine was put into a retort placed in a sand 

 heat, and eight fluid ounces were distilled over, which by 

 saturation with dry subcaii)onaie of potash afforded about 

 three fluid ounces of tolerably pure spirit floating on the 

 surface, 



I repeated this distillation precisely under the same cir- 

 cumstances, and mixed the distilled liquor with the resi- 

 duum in the retort, conceiving that, if the spirit were a pro- 

 duct, I now should have no difficulty in separating it from 

 the wine by the addition of subcarbonate of potash : but 

 although every precaution was taken, no spirit separated : 

 A portion of the subcarbonate, in combination with some 



* .Yn~!#.'« de Chiatje, tome xxii. p. 303. 



of 



