65 ities 
: DIAPHORETICS. 
eee 
Medicines which augment the natural transpi- 
ration of the skin. They are divided into two 
sections, according to the moderate or high grade 
of their action, called diaphoretics and sudorifics. 
Those which excite the skin so slowly, that its per- 
spirable fluid may be evaporated by its contact with 
the air, and thus rendered insensible to observa- 
tion, except by the soft state of the surface, or by 
very close inspection, are refered to the first sec- 
tion, Those which produce that copious fluid 
discharge, which we call sweat, are disposed of 
under the second. ‘The only difference «hich ap- 
pears to exist between these substances, is in their 
mode of acting on the exhalents of the skin. The 
same emunctories are liberated by both; but in the 
case of sweating, visibly and excessively. There are 
many methods of exciting the skin, which may all 
be comprised under three heads, physical, mechan- 
ical and medical. ist. By external and mechanical 
means. 2d, By internal agents which increase the 
velocity of the general circulation. and thereby ex- 
cite the action of all the parts of the bedy. sd. By 
internal medicines which do not dothis but enter the 
circulation, and thus reach the cuticular vessels; or 
merely stimulate some one, two, or more of the vis- 
cera, with which the skin sympathises, as for exam- 
ple. by adraught of cold water taken suddenly into 
the stomach, when the system is at par in its healthy 
excitement. For if it is otherwise the skin is not 
