ESSENTIAL SALT OP BARK. 
107 
The following is the mode of preparing it: 
Take Calisaya bark finely bruised, q. s. 
Put it into a displacement filter, with sufficient cold water 
to cover it — set it aside for twelve to twenty-four hours — 
then displace in the usual manner, until the strength of the 
bark is exhausted. Evaporate the clear liquor to the consist- 
ence of a soft extract, spread the same in layers over plates or 
evaporating dishes, placed over the gentle heat of a stove or 
sand bath ; continue a low heat until the extract is dry, sepa- 
rate the scales from the dishes, and having reduced the whole 
to fine powder, secure it in close vials, to prevent the absorp- 
tion of moisture. 
The product would probably be chiefly composed of kinate 
of cinchonia and quinia, and might no doubt be used with ad- 
vantage in many cases, instead of sulphate of quinia. No at- 
tempt has been made to analyse the febrifuge powder, (but a 
small quantity of which having been received in thiscountry,) 
the object being merely to present it to the meeting as a new 
remedy, and consequently a subject of interest, and at the same 
time to notice an old preparation of cinchona, which at least 
bears a strong resemblance to it in many of its sensible proper- 
ties, as the specimens of the two articles before you will at- 
test. 
Philadelphia, Fifth Month 9, 1842. 
VOL. VIII. — NO. II. 
14 
