and removed. The regular performance of these functions constitutes health, while any divergence from it, if not sufficient to be actual disease, at any rate tends towards that downward path which leads to disease.
The organs engaged in these three functions are—(1) The digestive organs, the mouth, gullet, stomach, and bowels, by means of which food is taken into the body and prepared for use; (2) The circulatory, by means of which the prepared food, having been absorbed into the blood, is carried through the arteries to the various parts of the body to form new tissue, while the old and worn-out tissue is carried away through the veins; and (3) The excretory, the lungs, skin, and kidneys, by means of which those waste matters pass out of the body. As far as the subject of clothes is concerned, we have to deal chiefly with the circulatory system in its relation to the skin.
The circulation of the blood is carried on by means of the heart, arteries, and veins.
The heart is a very powerful muscle, which acts as a kind of pumping machine; it is divided down the middle, by a muscular partition, into two parts, called the right and the left side, and no blood can pass from the one side into the other.
The right side of the heart receives the impure blood from the veins, and also the prepared food or chyle from the lymphatics, which there mixes with the venous blood. This mixture is then pumped by the heart into the lungs, through what is called the pulmonary or lung artery, which
