prompted nervous c 
reilly ba i tie 
‘Some narcotics, as opium, have, i in certain cases, effects 
ly These are, where increased discharges al 
irritation, in which, by diminishing irritability, they lessen 
charge ; but such an operation is altogether different f 
real astringents. Fins til 
As remedies against disease, astringents inay sometin 
their moderate stimulant operation, be substituted for tonics 
have thus proved successful in the tre \ 
and in all cases of debility, they"seem to be serviceable, ind 
dent of their power of checking debilitating evacuations. 
It is, however, for restraining morbid evacuations, that a str 
are usually employed. In the various kiads of hemor &e, 
they are frequently employed with advantage, though their poweris 
also often inadequate to stop the discharge. Indiarrheea they dimi- __ 
~ nish the effusion of fluids, and atthe same time give tone to the in- = 
testinal canal, and thus remove the disease. In the latter stage of 
dysentery they prove useful by a similar. operation. An profuse 
sweating, and in diabetes, they are frequently sufficiently powerful © 
to lessen the increased discharge ; and in those kinds of inter 
tom termed passive, and even in cortaio cases of active i 
tion they are applied with advantage as topical remedis 
It is an obvious coutions that astringents ar 
VEGETABLE ASTRIN GE 
Avicingmncy in vegetables seems to a Chanected witke a raids a 
chemical principle, or at least with some peculiarity of composition, ; 
- since vegetable astringents uniformly possess certain chemical pro- 
perties. The astringency is extracted both by water and alco- 
hol, and these infusions strike wblack color with any of the saltsof : 
iron, and are capable of corrugating more or less pores dead ; 
animal matter. = 
Chemical investigations have accordingly dincoyetet two Getinet 
in the vegetable astringeats, one or both of which may 
~ 
_ prob ly give rise to the astringent property. One of these, the 
Gallic acid, is distinguished ay its property of striking a deep black 
color with the salts of iron: the other, the tanning principle, or 
tannin, is characteriz ry * strong attraction to animal gelatin, 
-with which it combines, and forms a soft d ‘Mass, insoluble in - 
water. These may be separated by a solution of animal jelly, which 
unites with the tannin, and leaves the gallic acid pure. 
_ As both these principles exist in all the stronger vegetable lei 
“gents, it is probable that the corrugating property by which ie 2. 
action of these substances, as medicines, is modified, depends on — Fe 
_ Ee icaine, reels as, roe action on dead a - 
