266 
THE VETERINARY ART IN INDIA. 
Of Diuretics. 
From what has been already said on the subject of the sto- 
mach of the horse, it is obvious that we can place little dependence 
on the operation of medicine in that viscus ; we are, therefore, 
led to seek some other channel by which we may reduce the 
system under certain medical influence : this may be effected by 
the kidneys. 
They are two large glands, situated under the loins. They 
are employed to secrete the more watery and saline parts of the 
blood. Any medicine possessing the property of increasing* this 
secretion is termed a diuretic. 
They secrete two kinds of urine — one from the blood, which is 
saline, deep-coloured, and small in quantity, and voided when 
the animal drinks but little ; the other is produced by drinking 
large quantities of fluid, the watery part of which pass off* very 
soon, slightly impregnated with the former kind. 
I think it very possible that there are two modes by which 
diuretics produce their effects. The first is by simple stimulus 
acting on certain branches of nerves in the stomach, which are 
connected or act by sympathy with those in the kidneys ; thus, 
on a certain stimulus being applied to the stomach, an irritation 
of the kidneys may be produced. This is the more probable, 
from the very numerous branches with which the stomach, in the 
human subject particularly, is supplied. They may act on the 
same principle as immerging the hand in cold water on getting 
out of a warm bed, when a sense of stimulus will be conveyed to, 
perhaps, every part of the body, by the connexion of the nerves, 
and the bladder is also immediately stimulated to contract. This 
is further exemplified in cold weather, when much more urine is 
secreted than in warm weather. 
Medicines, also, which affect the kidneys, generally increase 
perspiration, and have the character of deterging the lungs, 
which, I think, is a further proof that diuretics may act without 
being conveyed to the kidneys, and merely by sympathy. This is 
a subject which would afford a much more ample scope, if the 
limits of the present work would admit of it. 
The second mode by which diuretics may produce their effects 
(though slower than the former, is yet much more rapid than by 
the usual and tedious progress of the chyle), and which I ima- 
gine to be the customary mode of operation, is perhaps as 
follows : — 
Most articles which have diuretic properties, independent of 
the first kind described, are more or less volatile and penetrating, 
generally the produce of the vegetable kingdom, and containing a 
