The intestinal mucous membrane, especially in the rectum, the duodenum, and a small portion of the small intestines, was of a violet red colour. It was inflamed in longitudinal stripes and in patches, which gave a mottled appearance, even to the outer surface of the intestines, before they were opened. This discolouration was not accompanied by any thickening of the tissues, nor by ulceration, and appeared rather the result of ecchymosis or hæmorrhage. The lining membrane of the rectum was principally affected, and its mucous glands were swollen and very prominent. This intestine contained puriform fluid, resembling the matter evacuated before death. The other intestines contained a very thick greyish white mucus. The mesenteric glands were inflamed, and appeared as if infiltrated with blood. The gall bladder was mottled on its surface by brown and violet patches, and contained black, thick, ropy bile, resembling melted tar. EXPERIMENTS XVI AND XVII. _Shewing the effects of the introduction of Mercury into an artery._ An ounce and a half of mercury, mixed with water, was injected into the left carotid artery of a sheep. The animal immediately evinced pain, and stood immoveable upon its feet. The head was held down, there was stupor and heaviness, and the eyes were protruded and widely open. The fore legs subsequently became bent, and the head inclined over the right shoulder with a kind of convulsive rigidity, which continued till death. Two hours afterwards, the animal became comatose, with some convulsive motions of the limbs, and the left eye became red and inflamed. Death took place fifty hours after the operation. _Post-mortem appearances._ The left eye was found in a state of suppuration, and contained mercury. Many of the branches of the left carotid artery also contained some mercury, which had not penetrated to the capillary system. All the organs supplied with these vessels were red, swollen, and inflamed, in consequence of the presence of the foreign matter. The thyroid gland, the tongue, the cheeks, and the lips, were, however, only affected as far as the median line, leaving the opposite halves pale and in their natural condition. A drachm and a half of mercury, mixed with some warm water, was injected into the crural artery of a large dog. The animal evinced no pain, and walked resting slightly on the affected limb, which became sensibly colder. After the expiration of an hour, the animal refused its food, became restless, and indicated severe pain in the limb, which was now very hot. On the following day, the leg was swollen and oedematous. On the third day, there was extreme thirst, increased oedema, and great suffering. The animal was killed sixty hours after the operation.