THE VETERINARY ART IN INDIA. 
575 
The food is first received in a cavity of a funnel-like shape at 
the upper part of the throat, called the pharynx, which, contracting 
on its contents, propels it through a passage (the oesophagus) into 
the stomach. In the oesophagus the insensible membrane (which 
extends to half the stomach) commences : this membrane is the 
principal cause that the contents of the stomach cannot be regurgi- 
tated as in vomiting. The oesophagus is always collapsed except 
in the act of swallowing, when it becomes extended to admit 
the passage of the food forced into it by the contraction of the 
pharynx ; consequently the insensible membrane, not contracting 
itself when the oesophagus contracts, it lies in loose folds, form- 
ing a kind of valvular structure at the entrance of the stomach, 
which prevents the food from repassing. 
This structure is also, perhaps, the reason that such violent me- 
dicine may be given without any great inconvenience, as it partlv 
defends the nerves of the stomach, which are very numerous. It 
is perhaps, too, from this insensible membrane that the stomach 
is so little liable to disease. 
The food, from the stomach, passes into a small intestine called 
the duodenum, where it becomes mixed with the bile and assimi- 
lates. From this it passes through the remainder of the small in- 
testines, which are very much convolved, and then enters a large 
intestine called the colon, which encircles all the other intestines. 
The curve which it makes to effect this very much retards its con- 
tents, particularly as it decreases very much in diameter as it pro- 
ceeds, insomuch that one part of this intestine, at some distance 
from its origin, loses nine-tenths in diameter. This will prove the 
cause of strong doses of physic being so dangerous ; for if a quan- 
tity of strong stimulus accumulates in this part of the intestine, the 
contraction will be such as to produce obstruction and inflamma- 
tion, which often terminate in gangrene and mortification. It is 
reckoned that upwards of a thousand horses are annually destroyed 
in England from too violent doses of physic, as most writers on far- 
riery, particularly a late author, recommends aloes in doses of eight, 
ten, or twelve drachms, with one or two drachms of calomel, jalap, 
&c., while Mr. Coleman finds three, four, or five drachms sufficient, 
with a drachm of calomel, in a cold climate ; and the consequence 
of exceeding this dose I have frequently observed when I was as- 
sistant surgeon to the 1 3th Dragoons, before I had studied the pre- 
sent branch of physic. The dose was then usually regulated by 
Taplin. At the cavalry depot at Maidstone, a horse had been phy- 
sicked as above, and in three days he died. On being opened, the 
contracted part of the colon was found to be obstructed, and most 
of the intestine was mortified. In the 13th Dragoons, horses after 
