The first difference is, that in cholera the sense of acridity in the throat does not precede the vomiting, as it sometimes does in poisoning. In cholera this sensation is caused by the vomited matter irritating the throat, or perhaps by the irritation in the stomach being propagated upwards by continuity of surface. But, whatever may be its cause, it is certain that the sense of acridity or burning sometimes remarked in cholera never begins before the vomiting. In many cases of poisoning, though certainly not in all, it is the first symptom.—The next difference is, that in cholera the vomiting is never bloody. I have been at some pains to investigate this point: and I have been unable to find any instance of the cholera of this country, which has been accompanied with sanguinolent vomiting; neither is such a symptom mentioned in any accounts I have read of malignant cholera. This article of diagnosis will, of course, be open to correction from the experience of other practitioners. Lastly, a material difference is, that the simple cholera of this country very seldom proves fatal so rapidly as poisoning with the irritants usually does. Death from irritant poisoning is on the whole seldom delayed beyond two days and a half, and frequently happens within thirty-six hours, sometimes within six hours, or even less. Malignant cholera frequently proves fatal in as short a time; but with regard to the cholera of this country, I believe it may be laid down as a rule hitherto unshaken by all the controversy to which the subject has given rise,—that death is not often caused by it at all, and that death within three days is very rare indeed. A few cases of death within that period, nay, even within twelve hours, have certainly occurred; but their great rarity is obvious from the fact, that many practitioners of experience have not met with a single instance, and others with only one case in the course of a long practice. Dr. Duncan, senior, mentioned to me a case, the only one of the kind he had met with, which commenced soon after the individual ate a sour orange in the Edinburgh theatre, and which proved fatal in twelve hours. Dr. Duncan, junior, also met with a single case, which was the instance already noticed of cholera produced by drinking cold water. Dr. Abercrombie also once, and once only, met with a case fatal within two days.[161] Mr. Tatham, a late writer on this subject, met with an instance which proved fatal in twelve hours.[162] Dr. Burne of London has likewise related an instance of death within fifteen hours occurring in a child.[163] And I was informed in 1831 of a case at Leith which ended fatally in twenty-six hours, and was at first supposed by the unprofessional inhabitants of the place to be an instance of epidemic or malignant cholera. My colleagues, Drs. Home, Alison, and Graham, never met with an instance fatal in so short a time as two or three days; at a meeting of the