boullay's filter, etc. 
affords a limpid product, that will keep twenty-four hours 
without alteration. 
I had frequently essayed in vain to filter these decoc- 
tions beneficially, until by the trial of this method, I am 
happy to add my testimony in favor of Messrs. B.'s asser- 
tion. 
Another great advantage is, that in thus treating vegetable 
matters with cold water, your extractive liquid is in a great 
measure divested of coloring matter, fecula, resinous, and 
other inert organic principles. Moreover, by this species of 
filtration the requisite quantity of menstruum can always be 
obtained, when otherwise, even while assisted by powerful 
mechanical pressure, a portion is lost by being retained in the 
residuary mass. 
The more fully to exemplify the advantages, I have prepared 
a tabular view of the results of the experiments made by 
these gentlemen. 
VOL. IV, NO. J. 
2 
