American Woman's Home: Or, Principles of Domestic Science; / Being a Guide to the Formation and Maintenance of Economical, Healthful, Beautiful, and Christian Homes

by Catharine Esther Beecher; Harriet Beecher Stowe

[Illustration: Fig. 58.]
[Illustration: Fig. 59.]

At Fig. 59 is a magnified view of another set of vessels, called the lymphatics or absorbents. These are extremely minute vessels that interlace with the nerves and blood-vessels of the skin. Their office is to aid in collecting the useless, injurious, or decayed matter, and carry it to certain reservoirs, from which it passes into some of the large veins, to be thrown out through the lungs, bowels, kidneys, or skin. These absorbent or lymphatic; vessels have mouths opening on the surface of the true skin, and, though covered by the cuticle, they can absorb both liquids and solids that are placed in close contact with the skin. In proof of this, one of the main trunks of the lymphatics in the hand can be cut off from all communication with other portions, and tied up: and if the hand is immersed in milk a given time, it will be found that the milk has been, absorbed through the cuticle and fills the lymphatics. In this way, long-continued blisters on the skin will introduce the blistering matter into the blood through the absorbents, and then the kidneys will take it up from the blood passing through them to carry it out of the body, and thus become irritated and inflamed by it.

[Illustration: Fig. 60]

There are also oil-tubes, imbedded in the skin, that draw off oil from the blood. This issues on the surface and spreads over the cuticle to keep it soft and moist. But the most curious part of the skin is the system of innumerable minute perspiration-tubes. Fig. 60 is a drawing of one very greatly magnified. These tubes open on the cuticle, and the openings are called pores of the skin. They descend into the true skin, and there form a coil, as is seen in the drawing. These tubes are hollow, like a pipe-stem, and their inner surface consists of wonderfully minute capillaries filled with the impure venous blood. And in these small tubes the same process is going on as takes places when the carbonic acid and water of the blood are exhaled from the lungs. The capillaries of these tubes through the whole skin of the body are thus constantly exhaling the noxious and decayed particles of the body, just as the lungs pour them out through the mouth and nose.

It has been shown that the perspiration-tubes are coiled up into a ball at their base. The number and extent of these tubes are astonishing. In a square inch on the palm of the hand have been counted, through a microscope, thirty-five hundred of these tubes. Each one of them is about a quarter of an inch in length, including its coils. This makes the united lengths of these little tubes to be seventy-three feet to a square inch. Their united length, over the whole body is thus calculated to be equal to twenty-eight miles. What a wonderful apparatus this! And what mischiefs must ensue when the drainage from the body of such an extent as this becomes obstructed!

But the inside of the body also has a skin, as have all its organs. The interior of the head, the throat, the gullet, the lungs, the stomach, and all the intestines, are lined with a skin. This is called the mucous membrane, because it is constantly secreting from the blood a slimy substance called mucus. When it accumulates in the lungs, it is called phlegm. This inner skin also has nerves, blood-vessels, and lymphatics. The outer skin joins to the inner at the month, the nose, and other openings of the body, and there is a constant sympathy between the two skins, and thus between the inner organs and the surface of the body.

SECRETING ORGANS.

Those vessels of the body which draw off certain portions of the blood and change it into a new form, to be employed for service or to be thrown out of the body, are called secreting organs. The skin in this sense is a secreting organ, as its perspiration-tubes secrete or separate the bad portions of the blood, and send them off.

Of the internal secreting organs, the liver is the largest. Its chief office is to secrete from the blood all matter not properly supplied with oxygen. For this purpose, a set of veins carries the blood of all the lower intestines to the liver, where the imperfectly oxidized matter is drawn off in the form of bile, and accumulated in a reservoir called the gall-bladder. Thence it passes to the place where the smaller intestines receive the food from the stomach, and there it mixes with this food. Then it passes through the long intestines, and is thrown out of the body through the rectum. This shows how it is, that want of pure and cool air and exercise causes excess of bile, from lack of oxygen. The liver also has arterial blood sent to nourish it, and corresponding veins to return this blood to the heart. So there are two sets of blood-vessels for the liver—one to secrete the bile, and the other to nourish the organ itself.

The kidneys secrete from the arteries that pass, through them all excess of water in the blood, and certain injurious substances. These are carried through small tubes to the bladder, and thence thrown out of the body.