338 Mr. W. Brande’s Experiments to ascertain 
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 the opportunity of examining many of the 
scarce wines enumerated in the table annexed to this Paper, 
I am indebted to the liberality of the Right Hon. Sir Joseph 
Baisks. 
Dr. Baillie, who took considerable interest in this investi- 
gation, was also kind enough to procure for me some port 
wine, sent from Portugal for the express purpose of ascer- 
taining how long it would remain sound, without any addition 
whatever of spirit having been made to it. 
Lastly, I employed raisin wine, which had been fermented 
without the addition of spirit. 
At a very early period of the present inquiry, I ascer- 
tained by the following experiments, that the separation of the 
alcohol, by means of subcarbonate of potash, was interfered 
with, and often wholly prevented by some of the other ingre- 
dients 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 subcarbonate of potash, afforded about 
three fluid ounces of tolerably pure spirit floating on the 
surface. 
I repeated this distillation precisely under the same circum- 
stances, and mixed the distilled liquor with the residuum in 
the retort, conceiving that if the spirit were a product, I now 
should have no difficulty in separating it from the wine by the 
addition of subcarbonate of potash ; but although every pre- 
