STRUCTURE, GROWTH,
AND
COLOUR OF THE HAIR.

CHAPTER VI.

In olden time, the hair was said to be produced by “a vapour or excrement of the brain.” In the more exact language of science it is described as a horny appendage of the skin. The skin is shown to be composed of two layers—the outer termed the cuticle, the inner the cutis. The cuticle is an insensible transparent membrane covering the whole surface of the body; the portion exposed to the air consists of flattened cells or scales which are continually being renewed; while on the inner surface, in contact with the cutis, is a soft mucous substance, in which are situate the pigment cells giving the characteristic colour peculiar to race and climate. The cutis is composed of the layer of minute papillæ, the principal seat of the sense of touch, covering an intricate arrangement of fibrous tissue, which receives the delicate ramifications of the nerves and arteries. The sheath from which the hair protrudes above the skin is formed by a tubular depression of the cuticle which reaches below the cutis to the subjacent fat and cellular tissue; the lower end of the sheath is shaped like a pouch, and contains the pulp from which the bulb and shaft of the hair are formed in successive portions—the most recent pushing forward that previously formed. The bulbs are larger in young than in old hairs, and are implanted obliquely in respect to the cuticle. The shaft of the hair being formed by an aggregation of parts, has been likened to a pile of thimbles one resting within the other; this overlapping of the outer coating of scales gives rise to that roughness which we feel on passing the fingers along a hair from the point to the bulb, though apparently perfectly smooth when held in the opposite direction. The colouring matter of the hair is seen in the pulp, and is distributed between the cells composing the shaft. In form the hair may be described as a flattened cylinder, not, however, hollow or filled with a kind of pith as is usually supposed; but solid throughout and formed of a homogeneous mass of a cellular texture. From the extreme minuteness of its structure, and the mystery which shrouds all vital processes, it is still a question as to whether the shaft of the hair is permeable by fluids derived from the blood. The old notion of a circulation within the hair like the sap in vegetables is disregarded; but it is contended that absorption does take place, and that fluids are transmitted to the extreme point of the hair. In proof of this we are referred to the sudden change of colour which the hair undergoes in extraordinary cases of mental emotion, as instanced in the sufferings of Marie Antoinette, whose hair was found to have turned grey with grief. It is assumed that the altered condition of the blood acting chemically upon the fluids of the hair destroys the colour. If this be granted, we must look for minor changes in the colour of the hair with every ordinary change in the normal condition of the blood. And we are told this does actually take place; that in health the hair is glossy, brilliant, and rich in hue; in ill health dry, faded, blank, and withered. But if this be so, and the connection between the blood and fluids of the hair be thus intimate, how comes it that partial changes of colour—this paleness of hue, and loss of brilliancy; and on the other hand, increased depth of colour consequent on renewed health—are not common phenomena and familiar to every one? Doubtless, we have still much to learn of the secrets of Nature, and there is yet something wanting to complete the revelations of the microscope, and the teachings of physiologists respecting the hair.

The palms of the hands and the soles of the feet are the only portions of the skin unfurnished with hairs. Their length and thickness varies considerably, from the softest down which is scarcely visible, to the long hair of the scalp and beard. The estimated thickness of a hair of the head is one-tenth of a line. Observations seem to show that flaxen is the finest, and black the coarsest hair. In females the hair of the head ordinarily measures from twenty to thirty inches, but in some instances it attains a much greater length; and mention is made of ladies whose hair has been two yards long and reached to the ground when they stood erect. The beard has been known to grow to the enormous length of nine feet: the portrait of a carpenter with a beard of this length, is preserved at Eidam; when at work he was obliged to pack it up in a bag. We are told the Burgomeister Hans Steiningen was thrown down and killed by treading on his long beard on the staircase leading to the council-chamber of Brunn. The long beard of John Mayo, a painter in Germany, is matter of history; he used to untie it in the presence of Charles V., who laughed heartily on seeing it blown about in the faces of the courtiers. Busbequius saw at Constantinople a janissary with such a quantity of hair on his head that a musket-ball would not penetrate it: we suspect there was some legerdemain in this case, and that the celebrated wizard was anticipated in his gun trick by some two hundred years or more. Some commentators have endeavoured to determine the weight of Absalom’s long and beautiful hair, but they differ widely in their computation; we are told that when its inconvenient length compelled him at times to cut it off it was found to weigh 200 shekels, which Geddes estimates at 112 ounces, and Clarke at 7-1/2 ounces—a conclusion in which nothing is concluded. Seven to eight ounces is held to be about the average weight of a lady’s tresses. With those who shave the beard its growth is said to be at the rate of six and a half inches per annum, so that in forty years a man must have cut off rather more than twenty feet of beard.

In the natural course, when the hair has attained a certain growth, it is thrown off, and its place supplied by a new growth formed from the pulp within the hair follicle. This process is continually going on, and is analogous to the shedding of the coat in quadrupeds, or the moulting of birds at certain seasons. The German physiologists, whose arduous and persevering labours in scientific research have never been excelled, have investigated with rare industry the minutest details respecting the growth of the hair; and one of them has accomplished the task of counting the number of hairs in heads of four different colours. In a blond one he found 140,000 hairs; in a brown, 109,440; in a black, 102,962; and in a red one, 88,740. Erasmus Wilson states that the superficial surface of the scalp may be taken at 120 inches, he averages the number of hairs per inch at 1000, which gives 120,000 for the entire head. It will be seen from the greater fineness of the blond hairs that the number is greater than those of red or black hair, and that red is the coarsest. The silken fineness of some shades of light hair is very remarkable, even the poets are evidently put to their wits end adequately to express its extreme fineness and beauty,—it is likened to the golden beams of day—and who has not seen the light playing upon it, and streaming rays and sparkles of lustrous beauty given out, as it were, from a diffused wave of sunshine—

“And on her hair a glory, like a saint.”

It is not clearly shown to what we must attribute the disposition to curl, which some hair naturally possesses. Some have thought that it was owing in a great measure to the presence of a considerable amount of oily matter in the shaft of the hair, which hinders the animal matter from attracting moisture which would have a tendency, it is said, to straighten the hair. But the more probable and more general opinion is that it mainly arises from the flatness of the hair. Now this flattening is sometimes very considerable, and the diameter of the hair two-thirds broader in one direction than in the other. The hair of the beard and whiskers exhibits the peculiarity most distinctly. In proportion to its size, the strength of a hair is very remarkable; one from a boy supported a weight of 7,812 grains; another from a man, 14,285 grains. The elasticity of the hair is very apparent, a hair 10 inches long has been stretched to 13 inches; and a hair stretched one-fifth of its entire length returns, with but trifling excess, to its first dimensions.

The chemical analysis of human hair, as given by Liebig, shows that its constituents are carbon, hydrogen, nitrogen, oxygen, and sulphur. Fair hair contains most sulphur and oxygen, and the least carbon and hydrogen; black hair the most carbon and hydrogen, and the least sulphur and oxygen. The hair of the beard contains more carbon and less sulphur than the hair of the head. The presence of sulphur occasions the peculiar odour of burnt hair, but we question the fact, as stated by some authors, that red hair is perceptibly redolent of brimstone. By experiments, Vauquelin obtained from black hair a whitish and a greyish oil; the whitish oil was also present in red hair, but the place of the greyish green oil was supplied by an oil; the colour of blood. Hair is one of the most indestructible of animal substances, even less perishable than the bones; this arises from the small quantity of water it contains, its chief bulk being made up of various salts of lime, iron, and manganese. In mummies more than two thousand years old the hair has been found unaltered, as may be seen in our own and other public museums. In the Abbey Church of Romsey, the hair of a female apparently of the time of the Normans was found perfectly entire on opening a coffin in 1839. It is in plaits 18-inches long, and preserved in a glass case, lying upon the same block of oak which has been its pillow for centuries. And somewhat recently, when the tombs of Gustavus Vasa and his Queen Gunilla, in the Cathedral at Upsal, were explored to gratify the longings of some worthy antiquaries; the hair of the Queen, which according to the popular annals was of extraordinary beauty, still remained—when ought else of earthly beauty had perished in the grave.

Hair is a non-conductor of electricity, and every one is familiar with the experiment illustrating electrical repulsion, which causes