252 
A TREATISE ON INGUINAL HERNIu®:. 
also teaches us, that the practice of castration, on which this 
difference depends, is a valuable prophylactic against this 
disease, as well as a subduer of certain violent propensities. 
Indeed, unless it be in parts of the country where racing is prac¬ 
tised, so rarely does hernia present itself, that the subject 
might appear to some to form a superfluous branch of the vete¬ 
rinarian’s education: we trust, however, that on the present 
occasion, our readers will take a more enlarged and en¬ 
lightened view of veterinary science; and we assure them that 
our present investigation will not be regarded to have been 
pursued in vain, should it prove to be the source of saving even 
but one horse in a practitioner’s lifetime from falling a victim 
to a dangerous but remediable disease. 
The present Treatise was presented in July, 1825, under the 
title of Memoirs, to the Royal Academy of Sciences. It is 
the result of numerous researches into inguinal hemiai; and is 
intended as a guide to the operator, pointing out to him that 
practice which is the most simple as well as the most success¬ 
ful. As a special dissertation on hernia, the work stands 
alone. The author conceives that he is the first who has elicited 
any fixed principles on the formation and treatment of this 
affection; and he ventures to hope that his anatomical and 
pathological details will sei’ve to establish them. 
Heruiae, or ruptures, are serious, frequently mortal occurrences, of 
which animals are much seldomer the subjects than man; not less on 
account of the horizontal position of their bodies, than from the dispo¬ 
sition of the muscles and tibrous envelopes forming the inferior parietes 
of the abdomen. In man, the intestinal mass is bearing downward, and 
particularly upon the inguinal regions, where the openings are situ¬ 
ated (the abdominal ring and crural arch), against which it is acting with 
unremitting pressure. In quadrupeds, on the contrary, in consequence 
of the oblique inclination forward and downward of the inferior surface 
of the abdomen from the Hank to the sternum, the intestinal mass gra¬ 
vitates against the diaphragm, pushing it forward, and occasionally rup¬ 
turing it. Furthermore, the particular organization of the muscular pa¬ 
rietes of the splanchnic cavity operates against the frequency of in¬ 
guinal or crural herniac. On reflecting the skin, first we meet with the 
panniculus carnosus; then a ligamentous covering corresponding to the 
fascia supcrficialis in mam but much more developed, much thicker, and 
more elastic, and particularly as it approaches the pubes ; next, the ex¬ 
ternal oblique muscle ; the internal oblique; the rectus; lastly,the fascia 
transversal is. The resistance oflered from the density and peculiar 
disposition of these coverings, explains why inguinal herniai are so un¬ 
frequent in monodactyles; \\ hy other herniae, such as crural, opturator, 
and pubic, are unknown; and why lacerations and herniae of the dia¬ 
phragm, so rare in man, arc so common in herbivorous animals. Another 
circumstance worthy of notice, inasmuch as it also contributes to re¬ 
strain inguinal herniae, is, that the greater proportion of horses become 
at an early age the subjects of castration; one of the consequences of 
which is, to contract, more or less, the inguinal canal; eryOf the predis¬ 
position to hernia of it. 
