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the lips than in the hands. Accordingly, when we wish to reciprocate the warmer feelings we are not content with the contact of the hands, and we bring the lips into the service. A SHAKEOF-HANDS suffices for friendship, in undemonstrative England at least; but a KISS is the token of a more tender affection.

Possibly it occurs to you that the TONGUE is more sensitive than either the hands or the lips. You have observed that it will detect an inequality of surface that escapes them both, and that minute, indeed, is the flaw in a tooth which eludes its searching touch. You are right. The sense of touch is more exquisite in the tongue than in any other part of the body; and to carry out my theory, it may be suggested that the tongue should be used for the purposes of which we are speaking. It is so by some of the lower animals. But, in man, this organ has work enough to do in the cultivation and expression of friendship in its own peculiar way; and there are obvious objections to the employment of it in a more direct manner for this purpose.

The Skin of the Hand.

By the aid of the accompanying drawings you will be able to form some idea of the structure of the SKIN of the hand.

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One of them (fig. 70) represents a section of the skin, made perpendicular to the surface, as

seen under the microscope. It is from the end of the thumb, and includes three of those delicate lines, or ridges that are found there.

The superficial, or uppermost strata (a and b), are the "Cuticle" or "false skin." The outer layer (a) is hard, horny, and dry. It is composed of numerous fine scales laid upon one another, like the tiles upon the roof of a house, but adhering more closely together, so as to form one continuous sheet extending all over the body. The outermost of these scales are continually being shed, peeling off as scurf, or being rubbed off; and fresh ones are supplied by the next layer (b), which is a softer material and lies immediately upon the surface of the "cutis" or "true skin."

This softer layer (b) is often called the "Rete Mucosum." It is made up of minute bags or bladders, named "cells" by anatomists, which grow and propagate upon the exterior of the true skin, being nourished by the blood in the skin. Those which lie nearest the cutis are the youngest and the softest. Gradually they are pushed outwards by their successors or offspring; and, as they approach the surface, they become flatter and drier and more adherent to one another, and are finally converted into the thin scales of the cuticle. Thus, there is no real line of division between the cuticle and the rete mucosum; but the cells of the latter

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are gradually transformed into the scales of the former.

The rete mucosum is thicker in the Negro than in the white man, and contributes somewhat to the softness of his skin. It contains also the colouring matter in the form of minute black particles diffused among its cells (fig. 72). These particles disappear, more or less, as the cells become changed into scales; hence the outer part of the cuticle of the Negro is not so dark as the rete mucosum, but, as it is transparent, or nearly so, it allows the dark colour of the rete to show through it.

Persons commonly speak of the cuticle as if it were the whole thickness of the skin. Thus, when a blister has drawn, they say the skin is raised; whereas it is only the cuticle. This is forced off from the skin by the fluid effused into its softer layer-i. e. into the rete in consequence of the irritating influence of the blister.

The cuticle has no nerves, and, therefore, no feeling. It may be cut or torn without pain. The snipping of a blister with the scissors is not felt, because the cuticle only is touched. It forms a covering to the whole surface of the body, and is invaluable as a means of preventing too great evaporation. Without it we should be dried up, almost mummified, by the end of a summer's day. It also protects the delicate sensitive skin under

neath. How sore is the knuckle when the cuticle has been rubbed off! The cuticle has, moreover, the accommodating property of becoming thickest where it is most wanted, as on the sole of the foot, and on the palms of the hands of blacksmiths, and artizans, and persons who handle the oar. And if any other part of the body be subjected to much friction, for instance, the knees of housemaids, or the shoulders of men who carry packs, the cuticle soon becomes thickened there.

Beneath the cuticle lies the "Cutis" or "True Skin" (c, fig. 70, and c and d, fig. 71). It is a tough structure consisting of interlacing fibrous and fine muscular tissue, and contains the bloodvessels and nerves. The cuticle may be pared off without any bleeding; but directly the skin is wounded the blood flows. The cutis does not present an even surface next the cuticle, but shoots out into a number of little finger-like processes, called "Papillæ," which project into the contiguous soft stratum of the cuticle, and are embedded in it. Thus the superficies of the skin is increased; and as the blood-vessels and nerves of the cutis are continued into the papillæ, they contribute very greatly to the sensitiveness of the skin. They are most numerous in parts where the sensitiveness of the skin is greatest; for instance, they are more numerous on the palmar, than on the dorsal,

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