[ i«4 ] 
with rectified fpirit of wine, prepared by heat. I 
found the filtered water, made ufe of to precipitate the 
refin, fo ftrongly impregnated, as to be more intenfely 
bitter than the watery infufions ; from whence I 
conclude, that fpirit difiolves not only therefinous, but 
the gummy part, more powerfully than water j and as 
it is a more expeditious way than common deco&ion 
or infufion, it might be more eligible for preparing 
the officinal extract. I have remarked too, that, after 
one luch extraction, the remaining bark is almofb 
wholly infipid, which (hows how great the extracting 
power of fpirit is, when aided by heat. In making 
this tinCture, it is neceffary that the ftopper be taken 
out of the phial, a little after it has been in the heat, 
to let the extricated air efcape, fo that it may after- 
wards continue flopped without any danger. 
XV. No- 
