149
if the bleeding' does not obscure them, still the distinction between the sac and great intestine, from this cause, is very difficult, and that the description of hernia I have now alluded to, is more frequent than has been supposed, I am strongly inclined to believe.*
While the blueness of the sac has been stated on the one hand, the dark colour of the intes- Dark comm
Dark colour.
tine has been adduced, as a criterion, on the other, and it is one of the best; but, in the first place, it may be observed, that it, too, is liable to be obscured; and, in the second, it not infrequently happens, that the sac is so thin, as to transmit the colour completely, and hence may lead to the most fatal mistakes.f Further, it is necessary to understand, that when the protruded part is either great intestine or omentum, the criterion will fail; because it rarely happens that these possess much depth of colour.
So much, then, for the evidence depend- Second mm
^ •11 -WKT fecconcl Ulftss*
ing upon sight alone. We must now consider some other points: and I shall commence with the consideration of the fluid which frequently exists in the sac, and which both serves to protect presence of the intestine, and, by its escape, informs us ^^^^ that the sac has been penetrated. Here, however, we may fall into error, for either there may be little or no fluid in the sac, as often occurs in femoral
- Remarks on cases of caecal hernia.
t Vide cases 3rd, 4th, 5th, 8th and 9th; also Sir C. Bell's cases, p. 204-7, &c. &c. Hey, p. 136, 141, 175, 182. Sharpe, p. 21. Scarpa, 61-2, 65.
