HAIRS AND FIBERS.

BY

JAMES F. BABCOCK.

THE presence upon weapons or the clothing of a defendant of hairs from animals or of various fibers used in the manufacture of textile fabrics has in numerous cases proved to be of great importance in trials for homicide. In the trial of Rubenstein for the murder of Sarah Alexander a fragment of corn-husk and a fiber of wool from the shawl worn by the girl, found attached to a blood-spot upon the boot of the defendant, proved to be very important evidence. Taylor gives the case of a woman accused of murdering her child, upon whose clothing were found spots of blood with hairs from a victorine worn by the victim. In the Piper case, in which the sexton of a church was tried and convicted of the murder of a child in the belfry, a single hair found upon the person of the defendant was claimed by the government to be identical with that cut from the head of the deceased.

Hairs found upon weapons or clothing may be from the head or other parts of the human body, or from some domestic animal. As in the case above cited, they may be from the fur of a very large number of animals, of which many varieties are used in different forms as articles of apparel. Fibers may be of silk, wool, cotton, linen, or a mixture of these in the various kinds of textile fabrics employed for clothing. The identification of hairs and fibers is, in most cases, conclusive and satisfactory-i.e., it can be asserted with certainty that a given hair is human or from some animal, and in most cases the animal, or at least, the class to which it belongs, can be determined.

The diameters, length, and peculiar markings of hairs when observed in the microscope furnish the means for distinguishing them. Indeed, these are practically the only data by which reliable conclusions can be drawn.

Hairs from the human body may be classed in three different varieties: 1. Long, soft hairs from the head, from one to three or more inches in length; 2. Short, thicker, and more rigid hairs from one fourth to one half inch in length, as in the eyelashes; 3. Short and very fine hairs from one twelfth to one sixth of an inch in length, as the down or woolly hairs from the face, back, or extremities. In the microscopic examination of hairs two structures are visible: a median, more or less dark, and somewhat irregularly granular portion, the medulla or pith; and an outer fibrous-looking portion, colored according to the color of the hair, the cortex or cortical portion. Under certain conditions of focussing, hairs from the head show a very light portion in the center, giving the appear

Microscopical Appearance of Hairs from Various Sources, and Vegetable and other Fibers. Figs. 22 to 35.-22, horse (back); 23, mouse: 24. cat: 25, chinchilla: 26, large hair from seal; 27, hair from head of female, age, eighteen; 28, hair from head of man after treatment with caustic soda: 29. fine hair from back of hand: 30, from head of child; 31, cross-sections of hairs from the head; 32, silk; 33, cotton; 34, flax; 35, wool. [J. F. Babcock-Del.]

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ance of a tube; but this is merely the effect of refraction, and disappears when the hair is examined after a preliminary soaking in a weak solution of caustic soda.

The diameters and lengths of hairs vary greatly, according to their position or the age or sex of the individual. Hairs from the head are usually longer, softer, and finer in females than they are in males. Hairs from children are softer and finer than those from adults. The long hairs from the head average about 1-350 of an inch in diameter in man and 1-450 in woman. The downy hairs from the body (lanugo) vary from 1-1000 to 1-3000 of an inch in diameter. Hairs from the eyebrows, the pubes, and the mustache are about 1-200 of an inch; on the back of the hand in man they vary from 1-250 to 1-500 of an inch. These figures are subject to considerable variations in different individuals, but may be taken as showing the comparative diameters of the hairs from different positions. Variations to a somewhat similar extent occur among animals. Most mammals have two or more varieties of hairs, one long, stout, and straight, and overlying others which are much finer and shorter. The peculiar markings and other appearances of these hairs may vary greatly even in the same animal, according to its situation, or whether they are of one or another of the varieties above mentioned. Figures showing the appearance of various animal hairs under the microscope may be found in the Micrographic Dictionary of Griffith and Henfrey (plate 29), and other drawings in the Proceedings of the American Society of Microscopists, 1884, p. 59, and in Woodman and Tidy's Forensic Medicine, p. 498.

Hairs for microscopic examination should be soaked in oil of turpentine and mounted in Canada balsam. The accompanying plate, together with the drawings to which we have referred, may be useful in determining the character of any particular specimen; but in all cases the latter should be compared with hairs of known origin before arriving at a definite opinion.

Silk fibers are cylindrical in form, and exhibit a strong refraction of the light passing through them; they are almost entirely devoid of markings of any kind or other peculiar structural appearances.

Wool has irregular fibers, and the transverse markings are very large and noticeable. Cotton has a spiral and twisted structure. Flax has fibers which are tapering toward the point, and they show joints at unequal distances. A solution of eosin or of any of the aniline colors produces a strong dye upon silk or wool, but upon cotton only a feeble and easily washed out stain.

No reliance can be placed upon conclusions drawn from the appearances presented by a single hair as to the identity of the individual to whom it belonged. This has been attempted in many criminal trials, with results almost invariably damaging to the side which has attempted it. All that can be fairly stated in such cases is that hairs from some particular head have a resemblance.

The reader may consult with profit a paper by William J. Lewis, entitled "Hair Microscopically Examined and Medico-Legally Considered," in Proceedings of the American Society of Microscopists, 1884, p. 59. Also articles by Lassaigne, Robin, and Orfila in Annales de Hygiene, 1857, 2d series, vol. viii., p. 226; 1858, 2d series, vol. x., p. 434; 1835, 1st series, vol. xiii., p. 466.

IDENTITY OF THE LIVING.

BY

ALLAN MCLANE HAMILTON, M.D.

TRIALS where instances of mistaken identity have been the issue are so numerous and curious as to form many of the causes célèbres of all times, and have reflected perhaps more upon the value of human testimony than any other influence. Plentiful cases upon record prove either how poor is the observation of the ordinary individual, or how common are certain appearances which have been looked upon as more or less striking peculiarities. Many interesting questions have arisen in connection with identification, not a few of which have formed the basis of legal proceedings, and the literature of medicine is full of dramatic instances of mistaken personality. While under some circumstances persons who have had ample opportunity for observation make the gravest errors in identification, on the other hand it is sometimes the case that a momentary glance in the shortest possible association has sufficed for a perfect identification.* It often happens with our own authorities that persons who have been robbed will readily pick out the guilty person from a score of others in whose company he may be placed; but possibly this facility is owing to the manner and anxiety of the culprit to escape detection as much as anything else.

The matter of systematic identification is largely a question of practice and skill, but in some measure depends upon the faculty of intuition, which, however, does not belong to many. It is certain that the power of unconscious observation is possessed by some individuals to a marked degree; and while these persons never forget a face, they are quite unable to explain their quickness or the means which enables them to reach a conclusion. An expert detective sergeant with twenty years' experience, who is known as having one of the best memories and the sharpest wits of the New York police force, tells me that he rarely looks at other

Considerable space is devoted in some works of this kind to the momentary recognition that often takes place where the only illumination is the flash of a pistol or the gleam of lightning. In many instances these examples are grossly exaggerated. Cauvet conducted a series of experiments, the conclusions of which are the following: (1) That the person firing a pistol may be recognized if the observer is placed very near him-say five paces-and at the side of the line of fire; (2) that he may be recognized when the discharge has been in a close place of small dimensions, and the observer is in a stooping posture or squatting; (3) that the chance of distinguishing the person firing is affected by the quality of the powder employed, the best English powder enabling the observer, when near or by the side of the person firing, both to see and identify him.