ON THERAPEUTICS. 63 
they cause the almost immediate absorption of such effusion, 
exert no influence against their redeposition? 
The practical observer, we are assured, will admit that 
they rather increase the tendency to effusion than diminish it. 
In certain cases it may happen that excessive secretion 
has become so habitual to a membrane or organ, that no 
medicinal agent, nor any therapeutic treatment, is perma¬ 
nently curative. 
In such cases, diuretics offer themselves as remedies, by 
the aid of which the patient may obtain a certain temporary 
relief; their use may be tolerated then, as may be the use of 
cathartics or stimulants, as a matter of necessity, or as a 
minor evil, producing some good at the cost of a gradually 
increasing harm. But not on these terms can we accept 
them as therapeutics. Even in the most acute forms of 
effusion in inflammatory oedema, and serous deposit from 
injury, we cannot see the advantage resulting from the use 
of powerful diuretics. 
On the other side, it is to be urged that the accumulation 
of fluid may be fatal, or that the vessels may so acquire the 
habit of secretion that it may ultimately amount to a new 
function in the part affected. Undoubtedly, this is true, nor 
would we for a moment underrate the importance of re¬ 
moving the effused fluid as rapidly as possible from any 
situation, and under any circumstances. We merely, on 
experimental grounds, object to diuretics as inefficient for 
this purpose. In the course of our treatment, tonics, 
dietetics, and exercise form the prominent means, with 
frictions, pressure, and embrocations when applicable. 
Accepting the aid of diuretics to a limited extent, we exhibit 
them in doses sufficient to excite an increased secretion, 
which may be safely continued for a considerable time 
without injury to the organs or to the system; giving a 
preference to those agents whose action is most diffused, as 
nitrate of potash and sulphates of soda and magnesia, in 
small doses, dissolved in the drink water. 
The advantages of diuretic action in cases of skin disease 
are presumed to depend upon a certain purification of the 
blood by their agency. Without questioning the influence 
of the kidneys in removing certain noxious matters from the 
system, we are not justified in assuming, under ordinary cir¬ 
cumstances, that medicines have the power of causing the 
elimination of impurities through these glands : the obnoxious 
principle is generally a sufficient stimulant in itself; witness 
the action of sugar in diabetes, and the expulsion of colouring 
matter of blood and bile in derangement of liver. No 
