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It is nothing more than Post Date: Tue, 19 Aug 2008 15:43:37 +0000 At the mouth, anus, and other natural apertures, it is continuous with the epithelium or cuticle of the mucous membrane. Under the microscope, the cuticle consists of several suc- cessions of small, hard, dry laminae or scales, each of which contains opaque spots of the original nucleus and cells, now flattened into scales, of an irregular form, overlapping each other at their edges, and constantly desquamating or falling off like particles of bran. It is nothing more than the secreted fluid from the cutis-vera, thrown out, it would seem, like varnish over the whole surface of the body, and then condensing and hardening into the scales just men- tioned. Autor of the post: Undefined When this layer is completed Post Date: Tue, 19 Aug 2008 15:29:48 +0000 The process of formation is thus seen by the microscope. The capillaries of the cutis-vera throw out lymph, contain- ing numerous cell-germs ; these soon enlarge into cells, and closely apply themselves to the surface of the cutis. When this layer is completed a second layer forms beneath, and the first then becomes separated from the true skin, changes its form and consistence, becomes flat and hard, and, by evaporation, dry and firm, and finally falls off in scales ; and this succession of changes, from the primitive secreted nucleus of the cell germ, up to the dry flattened desquamating scale, is continually going on. Autor of the post: Undefined When dry, its volume Post Date: Tue, 19 Aug 2008 15:12:36 +0000 The cuticle is flexible, elastic, and easily torn. Boiling water extracts some gelatine, renders it white, opaque, and deprives it of elasticity. When dry, its volume is di- minished, becomes firmer, slightly yellowish, and resists putrefaction for a long time, Fire causes it to burn like horn and emit a similar odor. Autor of the post: Undefined The skin thus constituted Post Date: Tue, 19 Aug 2008 15:01:39 +0000 The fixed alkalies resolve it into a soapy substance. Nitric acid turns it yellow almost immediately, and thickens, softens and reduces it to a pulp in twenty-four hours. The skin thus constituted of the cuticle, rete-mucosum, and cutis-vera, has its external surface moistened by two kinds of fluids the one watery in its nature, called the perspiration the other unctuous in its character, and known as the sebaceous. Autor of the post: Undefined The sebaceous or oily fluid Post Date: Tue, 19 Aug 2008 14:41:51 +0000 The perspiration, which, when augmented in quantity, becomes the sweat, is furnished by follicles called the sudo- riferous or sweat-glands, they are found in all parts of the skin, are of a round form, and consist of a co3ca, ending in a spiral tube, the exhalent duct, which passes through the cutis, rete-mucosum, and cuticle, open- ing on the latter by a minute pore. In the axillae they are described as large, very distinct, and, by their reddish color, readily distinguished from the fatty grains adjoining them. The sebaceous or oily fluid comes from sebaceous glands. Autor of the post: Undefined In the scalp the lobes Post Date: Tue, 19 Aug 2008 14:24:26 +0000 These, though not so numerous as the perspiratory, are nevertheless abundant in many parts of the skin, as the nose, face, arm-pits, arms, c; the palms of the hands and soles of the feet being destitute of them. They present a variety of form, from the simple sac-like follicle to the lobulated gland. In the scalp the lobes are clustered to- gether like a bunch of grapes ; and their ducts, which are straight, though sometimes spiral, besides perforating the skin, have one or more of them entering the hair follicle. Autor of the post: Undefined The meibomian glands Post Date: Tue, 19 Aug 2008 14:13:37 +0000 (Fig 19.) These ducts are lined by the involuted cuticle. The meibomian glands of the eye-lids, and the ceruminous glands of the ear, are also examples of sebaceous glands. Autor of the post: Undefined He says they are well Post Date: Tue, 19 Aug 2008 13:55:14 +0000 The sebaceous glands are about the size of millet seed, of a yellow color, and most generally situated, as well as the perspiratory, in the subcutaneous cellular structure, though sometimes imbedded in the dermis itself. There is another set of glands belonging to the skin, called the odoriferous glands, (glandules odoriferse,) which are very particularly described by Dr Homer, who seems to have given them more attention than any previous anatomist. He says they are well developed in the negro, and are found in the arm-pit, near the skin, and enveloped in cellular adipose structure. Autor of the post: Undefined The Functions of the skin Post Date: Tue, 19 Aug 2008 13:42:28 +0000 About three hundred of these glands were counted on a space the size of a Spanish dollar ; they are described as of a brown color, of varying size, from a line to two lines in length, and having a gran- ular surface, like the mammary and pancreatic glands. Their use is believed to be to furnish the odorous secretions of the body. The Functions of the skin are those of Sensation, Secre- tion, and Absorption. Autor of the post: Undefined This warning is Post Date: Tue, 19 Aug 2008 13:32:03 +0000 Sensation, as already stated, is either general or special every part of the skin being supplied with nerves so, in every part we find common sensibility, or tact, while spe- cial sensibility, or sense of touch, is very limited, confined almost exclusively to the tips of the fingers. By this func- tion the health and preservation of the body is particularly looked after ; it stands, as the faithful sentinel, on the out- posts of the system, giving immediate warning whenever an enemy is at hand, or an injury is suspected, whether by mechanical or chemical violence or the temperature of the atmosphere. This warning is by the sensation of pain. 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