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665 workers, hairdressers, grocers, electro-platers, brass- tube moulders. Dr. F. E. FREMANTLE (President of the Section of Epidemiology), proposing a cordial vote of thanks to the speakers, referred to the value of the Society as a body of experts to whom the Government could refer on subjects such as that now discussed. He hoped this would be done in the future in increasing degree. MEDICO-LEGAL SOCIETY. AT a meeting of this Society on March 21st, the chair was taken by Sir WILLIAM WILLCOX, the President, and a paper on the INVESTIGATION OF FiBE-ARM INJURIES was read by Prof. SYDNEY SMITH. The investigator, he said, often wanted to know whether a given injury was due to fire-arms or not; the type of fire-arm responsible ; the direction taken by the shot, and the distance of the muzzle from the body. Sometimes it was necessary to say whether one particular weapon had been used. The effects of fire-arms were very variable ; a rifle bullet at the beginning of its tra- jectory, before it had settled into its regular spin, would wobble and cause a wound like a severe explo- sive injury ; similarly a spent bullet, turning over and over, would cause injuries quite unlike those of a bullet wound. A small high-velocity bullet bored a clean hole; a slow large bullet often made a ragged one. Besides the projectile, the weapon produced a wave of gas, wads, unburnt powder, smoke, and flame, all of which (when the discharge was close enough) left their distinctive marks to aid diagnosis. Powder made tattoo-like marks on the skin, and left traces which could be chemically analysed. At a slightly longer range the wound made by a rifle bullet was a round, clean, punched-out hole surrounded by a zone of tissue denuded of its epithelium but showing little sign of blackening or burning ; outside this there might be powder-tattooing. The hole itself might be surrounded by a black ring due to fouling from the bullet; this was sometimes mistaken for powder- marking. Local bruising due to hydrostatic pressure was also apt to be mistaken for the marks of a close discharge. These distinctions were important, as they might turn the scale between the theories of suicide or murder. Automatic pistols caused very much less blackening and burning than any other type of weapon, because of the completeness of the combustion of their " smokeless " powder. They produced a typical clean entrance wound. Exit wounds were nearly always torn, as the bullet was forced through the tissues. A low-velocity bullet caused the same kind of wound that might be made by a poke from a stick. In bone, such as that of the skull, the entrance was clean-cut and the exit had an excavated appearance. A line between entrance and exit, if produced, nearly always gave a good indication of the track of the bullet, but deviation sometimes occurred within the body if the projectile struck a bone. The appearance might give a guide to the direction ; when the bullet entered at an angle the wound tended to be oval, and if the discharge had been at close range there might be much bruising and burning on the angle of fire. A shot-gun dis- charged within one yard caused a single wound, and within three yards slight scattering with burning and blackening, but above that distance the wounds of the separate shot were discrete and there was little discoloration. A sharp-pointed bullet might often inflict a wound very like that of a stabbing weapon, but the latter when pulled out tended to disturb the tissues, and their outward deviation distinguished the stab from the bullet wound. In bone the excavation effect of the dagger would be both inwards and outwards. Bullet wounds made at an angle might simulate cuts, but some portion of the tissue was generally removed, and there was often denudation of epithelium and bruising. More- over, the bullet often left metallic traces. Bullets were sometimes marked by the cloth through which they passed. X rays were often valuable in demon- strating the absence of a bullet where the site of entrance escaped notice, or when great deviation had occurred within the body. When more than one injury was found it was important to pay careful attention to all the anatomical possibilities before deciding whether one projectile or more had been responsible. A bullet had been known to pass in a straight line through the back of a running man, through his abdomen, into the front of his leg, and remain embedded in the back of the leg. Identification of F’ire-a7°ryas. Even if no projectile were found, a chemical and microscopical examination of the traces of metal and powder at the wound might give a clue to the kind of weapon which had been used. Some powders were filled with barium or bichromate. If an auto- matic pistol had been used, cartridge cases were often found at the scene of the crime, and the marks on the sides of these caused by the action of the weapon- might be sufficient to identify one particular nre- arm. The distinguishing marks on a cartridge-case fired in an ordinary revolver were mostly on the base. A bullet which had passed through the bore of a weapon received not only the marks of the rifling, but also many minute scratches caused by individual faults. From the gross markings it was generally possible to tell the type of weapon which had been used, while from the smaller individual markings it was possible to prove whether or not a given weapon had fired the bullet. A bullet found in the body was weighed, had its specific gravity estimated, and its base examined for signs of the maker’s name. The tip sometimes showed other signs which might identify it. The murderers of Sir Oliver Lee Stack in Cairo had been detected entirely by this means, and certain instruments with which they had notched the tips of their bullets had been found with metal still adhering that was identical with that of the bullets used. The apparatus used for the identifica- tion of bullets consisted of two microscopes fitted with a common eyepiece, so that the images of the two bullets to be compared were shown side by side. For macroscopic examination bullets were rolled on a sheet of plasticine ; rifling was examined by taking a casting in sulphur and rolling the casting on plasticine. Bullets, however, were not always fired from weapons of the same calibre as themselves ; a small bullet might be made to fit a large barrel by wrapping it in paper. Some Extraordinary Projecfile8. Criminals had been known to pick up a bullet on a rifle range and fire it from a shot-gun. In one victim’s body the investigators had found two shilling-pieces ; the bullet had struck them when they were in his pocket and had driven them in without itself entering. A shot fired at a railway train had entered the dining-car and nearly killed an important personage. The projectile found had puzzled the officials, for it had appeared to be made of bronze, and to be roughly of 16-calibre. Many persons had been arrested, and all the guns in the district had been examined for traces of a bronze bullet. Closer examination, however, had shown that the projectile was flat on one side and rounded on the other, and that it had a splash of lead at its base. It had proved, in fact, to be a fragment punched cleanly out of a hinge of the table in the dining-car. The actual bullet had then passed through the door of the carriage. Traces of lead had been found, and also traces of some other substance which had at first been thought to be cupro-nickel and which had suggested a rifle bullet. This had thrown suspicion on the troops in the district, but analysis had proved the substance to be steel, a fact which had shown conclusively that the assailant had been the owner
