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his head, and another lodged in his brain. It was extracted and found to be cast from pewter. This was the only clew the police possessed. After a month or so, suspicion fell upon a shoemaker, who had borne illwill toward the cur/. On examining his house, a pistol and three bullets were found. Two chambers of the pistol had been dis charged, and the balls obtained resembled that extracted from the brain of the mur dered man. The shoemaker was arrested and tried, and the bullets presented, but they were not considered sufficient to con vict him, they being the only evidence. He would have escaped, had it not been for a young chemist who begged to be allowed to make an analysis. He received and weighed the balls, and found all weighed the same, although that extracted from the head of the cur/ was somewhat battered out of shape. Chemical analysis demon strated that they were exactly alike in chemical constitution, — even when subjected to the most delicate analysis, — and that they differed markedly from twenty or thirty other pieces of pewter. The con clusion arrived at was that no two speci mens of pewter are alike, as this metal is not made in the same way at different times, the proportion of its ingredients varying considerably. Chemistry undoubtedly helps us more ef fectually in the examination for poisons than in any other way. We may imagine how dif ficult the task must be when we take into account the small amount of some poisons that is required to destroy life. Taylor says : "This may be tested by the smallest fatal doses of some well-known substances. In one well-observed case, two grains of arsenic, given over a period of five days, destroyed the life of an adult. Supposing the whole of this quantity had entered into and re mained in the blood, it would have formed only the ninety-eight thousandth part by weight of that liquid; but as elimination and deposition go on simultaneously, the proportion in the blood at any given time

must have been much less than this; and yet there can be no doubt that the poison destroyed life by its action on the blood!" Of course analysis of this fluid is a difficult and delicate matter, and we are occasionally obliged to resort to the spectroscope. Preyer, of Jena, has done more with this instrument than almost any one else. Prussic acid spec tra present two well-marked absorption bands, which in size and position differ but little from those of normal blood. Oxalic acid gives one band in the orange on the left of the sodium line, and a complete absorp tion of the violet, indigo, blue, green, and most of the red rays. Some poisons, how ever, are eliminated very quickly from the system, and we are unable to detect their presence. Among these are the organic poisons which often defy detection. The color of the blood is sometimes markedly changed by poisons, becoming either purple, black, etc. Many notable cases figure in the annals of medical jurisprudence, demonstrating the difficulty of making distinction between ac cidental and intentional poisoning. With Wilkie Collin s's admirable theory of the "Law and the Lady " in view, we call to mind the really ingeniously constructed poisoning case. This fictitious case, like many real ones, suggests the fact that often the use of arsenic as a beautifier by vain women, or as a remedy by patients with cutaneous affections, sometimes produces the death of the user, and occasionally suggests criminal action on the part of relatives or friends. An example is quoted by Taylor : " A girl, nine years old, died after a short illness with obscure symptoms suggesting criminal poisoning. It afterward transpired that her step-mother, who was suspected, had used it in an ointment that had been applied to the scalp. Post-mortem examination revealed traces of poison in the internal organs; and the question arose, whether arsenic had been administered in the food intentionally, the step-mother being known to have maltreated the child. As