The skin is a beautiful and complex structure. It is made up of an outer layer called the epidermis and an inner layer, the true skin or corium, which rests upon a subcutaneous layer, composed principally of fat and connective tissue.

The skin is a beautiful and complex structure. It is made up of an outer layer called the epidermis and an inner layer, the true skin or corium, which rests upon a subcutaneous layer, composed principally of fat and connective tissue.

The epidermis is divided into four layers. It has no blood-vessels and no nerves, but is nourished by lymph which escapes from the vessels deeper in the skin. It is simply protective in nature.

The true skin is made up of two indistinct layers, which harbor a vast multitude of nerves, blood-vessels and lymph-vessels.

In the skin there are two kinds of glands, the sebaceous and the sweat glands. The sebaceous glands are, as a general rule, to be found in greatest numbers on the hairiest parts of the body and are absent from the palms of the hands and the soles of the feet. They throw off a secretion known as sebum, which is made up principally of dead cells that have undergone fatty degeneration and of other debris. The sebum serves as lubricant. It is generally discharged near or at the shaft of a hair.

The sweat glands discharge on the average from one and one-half to two pounds of perspiration per day, more in hot weather and much less when it is cool. They are distributed over the whole external surface of the body. According to Krause there are almost 2,400,000 of them. They carry off water and carbonic acid gas chiefly.

Functions of the Skin