Elementary anatomy and physiology : for colleges, academies, and other schools . elementaryanato00hitc Year: 1869 AND PHYSIOLOGY. 303 contents into the same pore in which the hair itself is lo- cated. This secretion is an oil which keeps the hair in a smooth and moist state. 530. Their Number.—The number of the hairs varies with the color and portion of the tody. In one case there were found on the same sur- face 147 black hairs, 162 brown, and 182 blonde. On a surface one fourth of an inch square the same author found on the scalp 293 hairs and on the chin 39. Layer from Scalp, a, Oil Glands
Elementary anatomy and physiology : for colleges, academies, and other schools . elementaryanato00hitc Year: 1869 AND PHYSIOLOGY. 303 contents into the same pore in which the hair itself is lo- cated. This secretion is an oil which keeps the hair in a smooth and moist state. 530. Their Number.—The number of the hairs varies with the color and portion of the tody. In one case there were found on the same sur- face 147 black hairs, 162 brown, and 182 blonde. On a surface one fourth of an inch square the same author found on the scalp 293 hairs and on the chin 39. Layer from Scalp, a, Oil Glands. I> 531. Their Distribution Hair c»Follic^ and Direction—They are implanted either singly or in twos or threes, or even four or five together, and their direction is rarely perpendicular to the skin, being, in a natural state, downwards. They may, however, be changed in their direction by persevering efforts, as is sometimes seen by the brushing of the hair away from the forehead. 532. Chemical Composition—Durability—They differ from most tissues of the body by containing ten per cent, of sulphur. This, together with the fact that they contain a large per cent, of nitrogen, accounts for the unpleasant odor given off while burning. They resist decomposition better than most of the tissues. Those of Egyptian mummies re- main quite unchanged. And it is owing to their durability that they are used as relics of departed friends. Fig. 295. 530. What is said of the number of hairs on the horly ? 531. How are they distributed, and what direction do they take? 532. How do they differ from most other tissues in chemical composition ? How durable is hair ?
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