That these were powder-grains were shown in court by picking some of them out, placing them on a glass, and igniting them with a galvano-caustic point. From those at ten feet no distinct flash could be elicited; from those obtained at eight feet distinct flashes were seen (Trans. New York State Med. Soc., 1881).
In the celebrated case of Peytle, brought in 1839 for the murder of his wife, who had been killed by two bullets entering near the nose, the eyebrows, lashes, and lids were completely burned, and a large number of powder grains were imbedded in the cheeks. Experiments being made in order to ascertain the distance necessary to produce these effects, it was found that the weapon must have been held within a distance of twelve inches.
Wounds of Entrance and of Exit.—A great deal has been written in time past about the peculiarities of the wounds of entrance and of exit, much of which cannot be maintained under expert criticism. It is true that the wound of entrance will usually be well defined, the skin slightly depressed and appearing as above noted. It is true also that powder-marks will appear about this wound rather than that of exit. Usually, too, the orifice of exit is larger, less regular, its edges everted slightly, with more or less laceration of the skin, and quite free from any powder-marks or evidence of burning. The depression at the border of the wound of entrance differs after some days, by which time the contused margins slough away, and its appearance is daily changed by a process of granulation providing the individual recover or live long enough. According to Dupuytren, the hole in the clothing is smaller than that made by the same bullet in the skin. These are all points worth remembering when fitting bullets into wounds which they are supposed to have made; but the conditions under which gunshot punctures occur are constantly varying, and the significance of local markings is mainly the product of experience, care, observation, and reasoning. Thus the shape of either of these wounds will depend naturally upon the integrity of the bullet and its original shape and dimensions. Matthysen’s experiments give the following: A pistol fired at twelve paces distance, with a ball 15 mm. in diameter, made a wound in chest of 8¼ mm. diameter, and at its point of exit at the back one of 10 mm. In two experiments at the same distance as above, the entrance wound was 4 mm. larger in diameter than that of exit, and when a larger ball with a diameter of 17 mm. was used the same results were preserved, both wounds being less in size than the ball which made them. A spherical ball will usually cause more loss of substance than a conical, while the latter will cause usually more irregularity of outline and may even give the wound of entrance a slit-like appearance. Complications may also occur from other sources; a single wound of entrance may give rise to two or more wounds of exit due to splitting of the bullet, or if the bullet have been divided and the larger part lodged in the bone, only the smaller portion passing out, the wound of exit may in reality be much smaller than that of entrance. Again, a bullet may split into fragments before striking the body, and of these one may enter the body, or one or more of them lodge. Multiple wounds are possible even from one bullet, as when it passes through two different parts of the body. Again, when two wounds, for instance, are discovered, one of them may be regarded as that of exit, when in reality they may be two wounds of entrance, neither bullet having left the body. So while it is possible in some cases to decide which is which, too much dependence should not be placed upon appearances of this kind, least of all until after a careful autopsy has been made.
Course of the Projectile.—When a bullet traverses a body the two apertures may be nearly opposite to each other, although the bullet may not have taken a direct course between them, having been deflected by tissues of varying density in its course. This leads to the mention of the effect of animal tissues upon the course of bullets, with which works on military surgery deal extensively.
The following is a remarkable illustration, yet authentic, of a devious path of a ball. In a duel with pistols between two students at Strasburg one fell, apparently mortally wounded in the neck, but recovered without feeling any inconvenience from his wound. It was found that the bullet had struck the larynx and had gone completely around the neck. It was taken out by simply making an incision over it. Other instances may be cited where bullets have made a circuit around the head, thorax, or abdomen. The ball may make a half circuit of the body and lodge or emerge at a point opposite that at which it entered, thus leading one to suppose that it must have passed directly through (Wharton and Stille).
As the writer of a chapter on the effect of projectiles of small-arms, in the Third Surgical Volume of the “Medical and Surgical History of the War of the Rebellion,” p. 709, says: “Such bullets attain great range and effectiveness as oppose least frontage of resistance to air; their velocity consequently is greater. Rotation upon their long axes tends to give them steadier flight and more direct course. By their pointed apices they pierce more easily the structures opposed to them. Such bullets, owing to the elasticity of the skin, make a wound of entrance perhaps a trifle smaller in diameter than themselves, while spherical balls are more likely to carry a portion of the integument in with them.”
The differences of structure and density of the muscle tissues and their aponeuroses encountered by a bullet in its passage materially influence the directness of its course unless its velocity be very great, while round bullets are the more easily deflected from their course. The track of a small conical bullet passing swiftly through a muscle is more cleanly cut than that made by a round bullet, but in all gunshot wounds there is usually found a regular canal, with lacerated walls, with more or less destruction along the area of injury, shading off concentrically until lost in healthy tissue. There is always loss of substance dependent on muscle tension or direction of the bullet, whether transverse or obliquely to the direction of the muscle fibres; the more fibrous structures are torn and lacerated or simply perforated, mainly owing to their different tension at the instant; their openings seldom correspond to those of the muscle tissues or those upon the surface of the body, because of the constant change in the relation of the parts due to muscle action. This makes it often difficult to follow the course of a bullet with accuracy. The irregularity of a bullet-track due to these causes constitutes one of the great sources of danger, since cavities and pouches thus formed give lodgment to foreign matter driven in with the bullet, by retention of which a fertile source of sepsis is maintained. Gunshot injuries of bone may be classified as contusions, simple fractures, partial fractures, penetrations, perforations, and complete fractures with more or less comminution or loss of substance, all of these, of course, in the surgical sense compound. These are all manifestations of mechanical force acting in accordance with established laws. On autopsy these will be ascertained, while one or more portions or all of a bullet may be found imbedded in or attached to some bone. The best illustration of such accidents will be found in the “Medical and Surgical History of the War of the Rebellion.”
Such questions as pertain to the position of the wounded person when shot or that of his antagonist, and other similar inquiries, can only be settled by reference to particular circumstances of individual cases. Position of the wound may help a little. A bullet-wound directly in the centre of the top of the head could scarcely be received by a person standing unless his assailant occupied an elevated position. If accompanied by evidence of severe blows by which the deceased might have been knocked down, it might show that he had been shot after falling.
Wounds by Small Shot.—Small shot rarely traverse the entire body unless discharged from such proximity as to make a clean, round opening. Paley relates the following instance: A boy was shot in the neck by the accidental explosion of his own gun, No. 8 shot. He died instantly. He was lying forward of the muzzle so that it was nearly in contact with the skin of the neck. A large round hole was produced, in diameter one and one-half inches, whose edges were slightly darkened by powder. The wound of exit at the back of the neck, at the third vertebra, was a mere slit in the skin scarcely an inch in length with the diameter placed vertically. The smallness of this aperture may have been owing to the greater part of the charge being lodged in the body. Dr. Lowe states that in some experiments it was found that a round aperture might be produced by a discharge of small shot at a much greater distance than that assigned by Dr. LaChese, namely, ten to twelve inches. Even admitting such exceptional instances, it will scarcely ever occur that a wound from a small shot can be mistaken for one produced by a leaden bullet.
De Vergie has shown that when the ball enters a portion of the body well covered with fat, this often protrudes between the edges of the wound and may alter its character. If clothing have been carried in some shreds of it may show upon the wound, and such fragments of texture will nearly always characterize the wound at once as that of entrance.