There is a variety of intestinal inflammation, observed only of late by pathologists,[171] but now well known, which bears a close resemblance to the effects of the irritants. It is a particular variety of ulceration commonly situated near the end of the small intestines, accompanied at first with trifling or insidious symptoms, and terminating suddenly in perforation of the gut. It begins with tubercular deposition under the mucous membrane in roundish patches. Then an ulcer appears on the middle of one or more of these patches, gradually spreads over them, and at the same time penetrates the other coats. At last when the peritoneal coat alone is left, some trifling accident ruptures it, the fæcal matters escape into the sac of the peritonæum, and the patient dies in great agony in the course of one or two days, or in a few hours. Such cases, if not distinguished by the symptoms, will be at once recognized by the morbid appearances. Perforation of the intestines, with similar symptoms, also takes place without the previous tubercular deposit, by simple ulceration of the coats.[172] Another form of intestinal inflammation may also be here particularized, because it imitates the effects of the irritants in the cases in which they prove slowly fatal. It is a form of aphthous ulceration of the mucous membrane of the alimentary canal, which appears to affect almost every part of it from the throat downwards, and begins commonly in the throat. I once met with a remarkable case in which it appeared in the form of little white ulcers in the back of the throat, and gradually travelled downwards to the stomach and from that to the intestines,—being characterized by burning pain in every one of its seats, and successively by difficulty of swallowing, by sickness, vomiting, and tenderness of the stomach, and finally by purging. Such cases resemble the slow forms of poisoning with arsenic. But they differ in attacking the several divisions of the alimentary canal in turn, while in the examples of poisoning with arsenic now alluded to, the whole canal from the mouth to the anus is affected simultaneously. Dr. Abercrombie has described a similar disorder, which he appears to have occasionally seen affecting both the stomach and intestines at the same time; but he seems to doubt whether it ever occurs as an idiopathic disease, or independently of some co-existing or preceding fever or local inflammation.[173] 10. _Inflammation of the Peritonæum_, or lining membrane of the belly, will not require many remarks. When acute, it is rarely attended in its early stage by vomiting; rarely also by irregular action of the intestines, and never by diarrhœa; and it is at once distinguished in the dead body by unequivocal marks of peritonæal inflammation, which are very seldom caused by irritant poisons.[174]