as 
‘is obvious that such an effect will be produced by any substance 
a of stimulating the secreting vessels of the kidneys. All the. 
saline diuretics seem to actin this manner. They are received ir 
the circulation, and, passing off with the urine, stimulate the ves- — 
sels, and increase the quantity secreted. ot eS 
There are other diuretics, the effect of which appears not to arise 
from direct application, but from an action excited in the stomach, — 
and agated by nervous communication to the secreting urinary 
ce a i The druretic operation of squill, and of several other vegeta- 
sto be of this kind. | . - 
Rae ee eee 
ere is still, perhaps, another mode in which certain substances 
ce a diuretic effect, that is by promoting absorption. Whena — 
quantity of watery fluid is introduced into the circulating mass, 
imulates the secreting vessels of the kidneys, and is carriéd off 
by the urine. If, therefore, absorption be promoted, and if apor- — 
tion of serous fluid, perhaps previously effused, be taken up, the — 
quantity of fluid secreted by the kidneys will be increased. In this — 
: way digitalis seems to act: its diuretic effect, it has been said, is 
greater when exhibited in dropsy than it is in health. ae 
The action of these remedies is promoted by drinking freely of - 
___ mild diluents. It is also influenced by the state of the surface of 
_ the body. If external heat be applied, diuresis is frequently preven- 
ted, and diaphoresis produced. Hence the doses of them should be 
1 the course of the day, and the patient if possible be kept 
rect effects of diuretics are sufficiently evident. They dis 
harge the w: ioe the blood ; and by that discharge they indi- 
_ rectly promote rption over the whole system. pee 
© Drepsy is the disease in which they are principa jee 
when they can be brought to act, the disease is remov: 
injury to the patient than it can be by exciting any other ev 
Ea 
in | 
* 
_ CLASS IX.—DIAPHORETICS. 
_ Drarvorerics are those medicines which increase the } 
exhalation by the skin. When this is carried so far as to be €0 
ou the surface, it forms sweat ; and the medicines prot 
named sudorifics. Between diaphoretics and sudori 
* 
