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262 one-half or even two-thirds. The more pronounced these symptoms, the graver is the prognosis. Urea (even during the incubation period) and uric acid are very much diminished, the former in severe cases falling to 1.5 grm. to the litre. The urine is almost invariably acid, depositing granular casts, and giving spectroscopic evidence of hæmoglobin. Bile pigments show themselves towards the end of the disease; their appearance is regarded as a favourable omen. Hæmorrhage from kidneys or urinary tract is not uncommon.

Delirium may occur, but is not an invariable feature. Usually, after the initial stage of restlessness and acute suffering, the patient becomes torpid, and perhaps taciturn. In bad cases, coma, subsultus, etc., may gradually supervene, the temperature rising as death approaches and even after death. At the outset the bowels are confined. In the second stage diarrhœa, perhaps of black material resembling the vomit, may supervene; or there may be actual hæmorrhage of bright-red blood from the bowel.

The well-known black vomit— always a grave symptom, but fortunately not by any means an invariable one— forms one of the most striking features of this disease. In the earlier stages of the fever vomiting of bilious matters is a common occurrence. This may subside, or, after a time, give place to a coffee-ground vomit which seems to gush up without straining or effort on the patient's part, and which gradually deepens in colour until it becomes uniformly black. On microscopical examination the vomited material is found to consist of broken-down blood corpuscles and altered hæmoglobin suspended in a yellowish mucoid fluid. This material is, doubtless, in the main derived from blood transuded through the walls of the capillaries of the mucous membrane of the stomach. It is intensely acid. Though the black vomit may not always be seen in fatal cases during life, it is invariably found in the stomach on post-mortem examination. Sometimes pure blood is thrown up from the