We have seen that the work done by the master tissues causes a loss, or produces a certain amount of waste material, consisting of Carbon, Hydrogen, Oxygen, and Nitrogen, and some mineral matter—salts. This loss or waste has to be replaced in quantity and quality sufficient in order to maintain a healthy condition of the body.

And, since we know the precise, or almost the precise, quantity of material excreted, which consists of Carbon, Nitrogen, Oxygen, and Hydrogen, etc., we can also estimate, with considerable precision, the quantity needed to replace it.

More than 41 per cent of the entire weight of the body is made up of muscular tissue. The nervous tissue constitutes not quite two per cent.

The chemical composition of muscular and nervous tissue—of the solid part only—is

Carbon. Hydrogen. Nitrogen. Oxygen. Sul.
51.56.915.220.90.3
to to to to to
54.57.317.023.52.0

The watery portion of the muscle is not mentioned. Please notice the large quantity of Carbon and the small quantity of Hydrogen in the composition of the solid part of the muscle.

We are aware that the muscles are always producing Carbonic Acid—that is, C and O2—and when a muscle contracts, there is a sudden and extensive increase of the normal production.

The blood that comes from a contracting muscle is richer in Carbonic acid—that is, it contains one atom more of Carbon and two atoms of Oxygen more.

The blood that has passed through the lungs changes from venous to arterial blood. The venous discharges about 5 vols. of Carbonic acid (C O2); the arterial carries away about 5 vols. of Oxygen (O) to the tissues.

The carbohydrates taken into the system: