So close and fine is this network in the skin, for instance, that, as you can readily prove, it is impossible to thrust the point of the finest needle through the skin without piercing one of them and "drawing blood," as we say, or making it bleed.
From this network of tiny, thin-walled tubes, the body-cells draw their food from the blood.
[Illustration: DIAGRAM OF ARTERY, CAPILLARIES, AND VEIN] The Meaning of Good Color.

It is the red blood in this spongy network of tiny vessels that gives a pink coloring to our lips and the flush of health to our cheeks.

Whenever for any reason the blood is less richly supplied with food or oxygen, or more loaded with "smoke" and other body dirt than it should be, we lose this good color and become pale or sallow.

If we will remember that our hearts, our livers, our brains, and our stomachs, are at the same time often equally "pale" and sallow--that is, badly supplied with blood--as our complexions, we can readily understand why it is that we are likely to have poor appetites, poor memories, bad tastes in our mouths, and are easily tired whenever, as we say, our "blood is out of order." The blood is the life.

Starve or poison that, and you starve or poison every bit of living stuff in the body.
THE HEART Structure and Action of the Heart.