THE PLUMBING AND SEWERING OF THE BODY The Wastes of the Body.

Almost everything that the body does in the process of living means the breaking down, or burning, of food; and produces, like every other kind of burning, two kinds of waste--"smoke" and "ashes." The carbon dioxid "smoke," as we have already learned, is carried in the blood to the lungs, where it passes off in the breath.

The solid part of our body waste, or the "ashes," is of two kinds--that which can be melted in water, or is, as we say, _soluble_; and that which cannot be melted in water, or is _insoluble_.

The insoluble part of our solid body waste goes into the feces and is thus disposed of.
The soluble part of the body waste goes by a somewhat more roundabout route.

With the carbon dioxid it is poured by the body cells into the veins, carried to the heart, and pumped through the lungs, where the carbon dioxid is thrown off.