The outer surface of the abdominal viscera is commonly either very vascular or livid, or bears even more unequivocal signs of inflammation, namely, effusion of fibrin and adhesions among the different turns of intestine; and these appearances may take place although the stomach is not perforated.[285] The cause of this appearance, which is seldom observed in poisoning with other irritants, more especially with the metallic irritants, is that the acid passes through the membranes of the stomach by transudation during life,—as will be proved immediately. It must be observed, that the peritonæum is sometimes quite natural after death from sulphuric acid, even although the stomach was perforated. I have seen this in a case which proved fatal in twelve hours. An important appearance in the abdomen, to which less attention has been hitherto paid than it deserves, is gorging of the vessels beneath the peritonæal membrane of the stomach and adjoining organs with dark, firmly coagulated blood, arising from the acid having transuded through the membranes and acted on the blood chemically. My attention was first turned to this appearance by an interesting case, which I saw in 1840 in the Royal Infirmary of this city, and of which an able account has been published by Dr. Craigie.[286] The whole vessels of the stomach were seen externally to be most minutely injected and gorged, and the blood in them was coagulated into firmly-cohering cylindrical masses, as if the vessels had been successfully filled with the matter of an anatomical injection. This appearance was also observed in the superior mesenteric arteries, in the omental vessels, and over the greater part of the mesentery. It was occasioned by the chemical action of the acid coagulating the colouring matter and albumen; for the clotted blood was strongly acid to litmus-paper. So too was the peritoneal surface of the stomach, omentum and intestines. And the acid had transuded through the stomach and into the omentum and tissues of the intestines during life; for in the first place, there was no perforation of the stomach, and secondly, I ascertained that there was no free acid either in the matter discharged from the stomach before death after the free administration of antacids, or in the contents of the stomach obtained at the examination of the dead body. The stomach, if not perforated, is commonly distended with gases. It contains a quantity of yellowish-brown or black matter, and is sometimes lined with a thick paste composed of disorganized tissue, blood and mucus. The pylorus is contracted.