Page:Letters to Mothers (1839).djvu/86

 physiology of the skin, the lungs, the circulation of the blood, and the digestive organs. I cannot flatter myself that I am imparting any thing new, when I mention that the former is composed of three laminae or layers, and that the inner one, is a tissue of nerves and blood-vessels, so minute, that the point of the finest needle cannot be introduced, without puncturing some of them. Through these ever-open, and invisible ports, the waste matter of our continually changing bodies escapes, equalling in weight, more than twenty ounces every twenty-four hours. This evacuation, if checked, so overtaxes other excretory organs, as to produce disease, and if retained on the surface, and returned through the absorbents, acts as a poison in the system. Daily and entire ablution, with correspondent friction, is necessary to preserve in a healthful state, an organ of such great importance to the animal economy.

The sympathy between the skin and lungs is so established, and intimate, that a neglected state of the former, has much to do with the production, and progress of pulmonary disease, that frequent and favourite messenger of death. Food, after being received into the stomach, sends forth its nutritious portions, in the form of chyle, to be mingled with the blood. This junction is formed at the right side of the heart, but the mixture of new and old fluid, is not fitted to sustain life, until