duced in the veins, which is adequate to the production of the phenomena in question.*

In men who have been hanged, there is an obvious cause of accumulation in the veins; and the same cause seems to act, in a smaller degree, in cases of ordinary death. It operates also, in death by drowning; but I have had no opportunity of ascertaining whether, in this case, the same appearance of stomach is produced, as in suspension. The striking vascularity so often observable in that organ after death, in consequence of venous accumulation, seems to be, in a great measure, referable to the peculiar laxity of the medium in which its blood vessels are placed, and to the great number with which it is supplied. Hence, likewise, the disposition which it exhibits to effusion of blood, as well during life as in death, from suspension.

The different degrees of colour, from dark purple to florid, which I have noticed as being seen in the vessels of the villous coat of the stomach, appear likewise occasionally in the veins of the mesentery and intestines. They afford examples of arterial hue, or a certain portion of it, continuing in blood, some time after the reflection of an artery into a vein. There are many facts which prove, that this change of arterial into venous blood may, under some circumstances, be accelerated or retarded in the living body; and Mr. Hunter has observed, that there is generally a palpable difference in the degree of darkness of venous blood, taken at different distances from its source in the arteries; for instance, at the hand, and the bend of the arm.t

The precise circumstances under which arterial colour is preserved after death, are not altogether known. The florid

* Etenim ubi cor sanguinem allatum in arterias promovere non amplius valet, illa vis (elastica) ad urgentem in venas sanguinem sufficit. At si vis ista elastica simul cum vita perditus v. c. arteria in os mutatur, arteria quoque post mortem sanguine plena conspicitur.'

SOMMERING De Corporis Humani Fabrica, tom. 5. p. 64. HUNTER'S Treatise on the Blood, Inflammation and Gun-shot Wounds,

p. 69.

hue seems to be an exception to that in which blood usually appears in the dead body; for there the arteries, (when they are not empty) as well as the veins, contain dark blood. This change from the proper colour of the blood contained in the arteries, is supposed, by M. Bichatt, to take place before death; for he is of opinion, that in most instances, for some little time previously to the extinction of life, the whole of the blood which circulates through the body, is dark; and that, where any surface after death is found to be florid, (and he instances the mucous membrane of the nasal fossæ as being occasionally so) it has continued in that state by means of its capillaries, which he conceives are not easily affected by changes which may have taken place in the circulation of larger vessels.

This conclusion, with regard to the capillaries, would merely provide for their continuance in the state in which they existed during life; but it is hardly reconcileable with the enlargement which, after death, is so palpably seen to have taken place in them, in the human stomach. Such enlargement can scarcely have been produced, except by a force sufficient to overcome the resistance made by the parietes of these minute vessels to the augmentation of blood; and for this force, it is difficult to look except to the arteries; particularly as those of middle and smaller size are, after death, found to be freed from blood. In this case, however, the blood last projected, might, if dark, have been expected to impart to such capillaries, a dark, instead of a light colour; which, in many instances, it has been seen, is not the fact.

The change from florid to dark coloured, or from dark to darker red, which, as I have observed, takes place in the colour of the minute vessels of the stomach, in the course of a short time, is in some degree analogous to that change, which Mr. Hunter has observed to occur, by rest, in the colour of arterial blood, whether contained in aneurismal sacs, in cellu

† Anatomie Générale, tom. 2.

lar membrane in consequence of extravasation from wounded arteries, or in the brain after apoplexy.*

The diffused redness, to which I have stated that the distinct vascularity of the villous coat soon gives place, occurs in a longer or shorter time, without any obvious cause for such difference. It seems to be the effect of transudation from the coats of the containing vessels; for I have seen, on inverting a vascular stomach, extending it upon a flat surface, and keeping it moist and undisturbed, that a blush is communicated from both larger and smaller veins to the contiguous cellular membrane, which very gradually increases in extent: while such parts of the villous coat as possess minute vascularity, lose it under such circumstances; the interstices becoming coloured by the transuding fluid, so as to give the whole of the surface an uniform crimson or purple tinge. The effect mentioned, I have observed to commence, in a recent stomach, in the course of a day, or a day and half, but sooner in one which is less recent, though not at all putrid. Putrefaction will doubtless increase, but it does not seem at all necessary to transudation. This diffusion of colour is, therefore, analogous to the transudation of the bile from the gall bladder, which is so very generally observed in the examination of bodies.†

The slight resistance which dead matter is able to give to a contained fluid, is proved (if more proof than what the gallbladder affords is necessary) by the employment of any two fluids, which are nice tests of the presence of each other. Thus, in a portion of inflated recent intestine, when the mesenteric arteries are carefully injected with solution of prussiat of pot

* HUNTER, 1. c. p. 65.

HALLER refers an appearance of transudation from the intestinal vessels of a female who died of erysipelas in the leg, to inflammation, though there is every reason to suppose that it occurred after death. "Intestina flatu insigniter distenta, tota inflammata erant, non quod vascula unice distenderentur, sed quod cruor secundum totam longitudinem arbuscularum vasculosarum in cellulositatem effusus, lineam obscure rubentem, in vasis circumpositam efficeret.”—Opera minora, tom. iii. p. 349, obs. 53.

ash, and the veins with solution of green sulphat of iron, no effect is perceptible for a short period; but very soon the blue colour is produced, in the whole course of both systems of vessels, to considerable minuteness, and at the same time. If the carotid artery, or a portion of intestine (both of them recent) be filled with either of those fluids, and tied, and the centre be made to dip into a small vessel containing a portion of the other fluid, it becomes very speedily tinged with blue precipitate, at the place of contact.

Are circumstances of vascularity affected by thinness of coats? The coats of the stomach vary very much in thickness in their different parts; the whole substance being sometimes so thin at the great end, as readily to admit of making out through it, dark figures on a light surface. In one case of this kind, the weight of two oval portions of similar size varied about three fourths: the portion taken from the fundus amounting to 5 grains, while that taken from a part about midway to the pylorus (where this stomach seemed to be thickest) amounted to 224 grains. This stomach admitted the injection of its arteries close to the part where a ligature had been placed round the oval orifice, without extravasation; and another stomach allowed the injection to pass, with the same success, over a portion, which, to judge by figures seen through it, was equally thin.

The veins, likewise, when pressed backwards, minutely injected their smaller branches, just as has been described to take place, in ordinary circumstances of venous turgescence, without any effusion being produced into the cavity of the stomach; for the blood, in the minutest extremities of these vessels, was incapable of being wiped off, or of giving any tinge to a white surface applied to the villous coat in which they terminated. This last mentioned circumstance, I have likewise frequently remarked, in cases where the great end of the stomach was nearly as thin, as in the stomachs above mentioned, if not equally so. Where there was, however, the slightest cut

in the villous surface, the vessels were divided, and consequently effusion took place.

The difference of thickness which occurs between different parts of the same stomach, is produced by variations both in its villous and muscular coats; for I found that of two equal oval portions of the same stomach, one of which was taken at the great end, and the other near the pylorus, in the lesser curvature, the former, weighing six grains, had its villous coat consisting of 21 grains, and the peritoneal and muscular together of 3 grains; while the latter, weighing 19 grains, had its villous coat consisting of seven grains, and its peritoneal and muscular together, of 12 grains.* The thickness of the peritoneal coat appears to be pretty uniform; but that of the muscular and villous to vary, not only in different stomachs,

* It may be proper to mention, that the weight of the villous, and of the peritoneal and muscular coats of nine similar oval portions of this stomach, was taken with some care, the dissection being made after separation from the stomach. In three other similar portions, the peritoneal and muscular coats alone were taken, the villous having been dissected off previously to removal. The following are the weights in grains, viz.

The thinnest portions were from the great end, the others from different other parts of the stomach, but the thickest were taken near the pylorus, particularly the heaviest portion (173). The mucous coat had been dissected from this portion before it was taken out, so that the united weight was not known; but it could not be less than twenty-four grains.-It is obvious that there are various sources of error in ascertaining, very correctly, the weight of such soft and yielding parts which are to be separated in equal portions. That there is a considerable difference in the quantity and proportion of each coat, in different parts of the same stomach, seems to be all that it is of any consequence to know.

I should imagine that it is but seldom there is so much disparity between the thickness of different portions of the same stomach. The great end is not unfrequently extremely thin.