Nutrition is that which takes place in the body of a live, healthy animal between the time when food is taken into its body and the time when the ash resulting from the combustion of the food is excreted.

Life is the phenomenon we call nutrition, or, vice versa.

We see an automobile or a train moving with all the grace and celerity of an ideally constructed machine, and we say that its mechanism is perfect; hence its nutrition is perfect. If we see it halting, coughing, puffing, and blowing, in an effort to move, we know that something has gone wrong with its nutrition, or its mechanism. When we see the machine at rest, we know that the life of the engine is killed, The phenomenon which in animals and plants we call nutrition, and motion in the case of machinery, is life.

The power behind all activity--the power that makes activity possible--is the sun.

A machine is a synthetical arrangement of properly constructed and adjusted parts. When all parts are ready, it will not move until the sun's rays are thrown upon it by way of oil, coal, or electricity, all of which represent static energy, or stored-up sunshine.

Those who hold the dualistic idea persist in teaching that there is a mysterious force behind and on the outside of nature that causes the phenomenon we call life. They will not admit that it is the sun. Such minds are not satisfied with a simple explanation; they must have an unexplainable, mysterious, or, as Spencer declared, an unknowable cause.

It is wonderfully consoling to have faith in something--to have something that faith can lay hold of. Such a something I have. But, while I myself can get rest and comfort out of it, I realize that the majority of people cannot. I do not ask anyone to give up his beliefs for mine; but certainly no one can be injured by allowing me to try to explain the cause of life that gives me satisfaction.

Those who never have taken a peep into the world that is above, below, and beyond their unaided sense-perceptions must feel their limitations and know that there is an Infinite existence which has not been revealed to them. They are right; but they have no right to declare that it has not been revealed to others.

The study of bones, flesh, and organs gives us an acquaintance with the animal, its mechanism and personality; but how its bones, flesh, and organs are constructed is quite another study; indeed, it is a world all to itself--a world hidden from common observation. Because of its infinitesimalness, this world is beyond the horizon of unaided sense-perception. On the other hand, the telescope and spectroscope reveal the infinitely large and distant.

To explore the regions where nutrition is going on, one must take one of the torch-lights of The Infinite--the microscope--and there will be revealed the mysterious--the handiwork of the Creator!

In the workshop of The Infinite there is a department where the rudimentary units out of which everything is made are evolved. They have but recently been discovered, and they are called electrons. For the sake of brevity, and to have a definite and inexhaustible source whence to draw a supply of electrons, we will say that the sun's rays are made up of electrons. So necessary a substance as the base out of which everything is made, should be everywhere: and certainly sunlight is everywhere.

In another part of The Infinite's workshop there is a place where cells are made. Cells are the units out of which living matter is made. The human body is made out of cells, the same as houses are made out of brick.

As stated before, we cannot observe The Infinite work unless we are aided by The Infinite's torchlight--the microscope. With this instrument we discover that the tissues of the body are made up of cells. To understand a cell, it will be well to examine some of the lowest forms of life.

The ameba is a colorless, single-celled, jelly-like, protoplasmic organism found in sea and fresh water. It is constantly undergoing changes of form, and nourishing itself from surrounding objects.

The white corpuscles of the blood perform ameboid movements--i.e., changes of form, consisting of protrusions and withdrawals of substance. (Gould's "Medical Dictionary.")

The ameba is found in mud and decaying vegetation at the bottom of pools of water. On examining a drop of this slime with a microscope that magnifies two or three hundred times, life is observed. A great variety of living forms are seen.

The ameba is the lowest type of cell-life. The structure of a cell is made up of a nucleus (a small nut) and a body which is composed of a substance known as protoplasm. In biology a cell is known as a bit of protoplasm containing a nucleus.

All tissues--nerve tissue, muscle tissue, bone tissue, and tissue of cartilage--are made up of cells. These vary in size, notwithstanding they are all microscopic. The microscope reveals the fact that there are characteristic forms of cells for each tissue; and, so far as known, all have a cell body and a nucleus.

The microscopic appearance of protoplasm is a colorless, semi-fluid substance, in which are seen solid particles, or granules. The nucleus is found near the center of the cell, and is composed of protoplasm denser than that of the cell body. The cell body may be likened to a bit of the white of an egg; but it should not be forgotten that the white of the egg is not living substance. The fertilized egg needs the sun's rays to add the missing link--to breathe into it the breath of life. The unfertilized egg needs a nucleus that is potentized with life. All the rest of the egg is body food, if you please.

An egg is not complete without the nucleus; and then, without the sun's rays, it can never take on life. This is true of the cells of a living body; for the sun's rays must be utilized to the extent of furnishing a pent-up heat of about one hundred degrees Fahrenheit, or these cells cannot renew themselves.

Nutrition is the principal attribute of matter. The phenomenon known as nutrition is life; and this life cannot continue to manifest without the properties imparted by the sun--electrons and heat. The sun, then, is the source of all life.

Assimilation means that the cell seizes upon the nutritive materials placed at its disposal, and groups them together into an organic synthesis--a molecule--that is very unstable. In order to do this, heat, or the sun's rays, or the electrons, must be furnished in sufficient quantity. Every cell of the body is an electric cell; all are connected into a whole instrument, or battery, represented by the cerebro-spinal system; and the refined output is mind.

The feeding and the waste of this wonderfully complex electrical apparatus take place in the cells, which are microscopic bodies, and which have the power to gather the electrons from the sun, and select other elements from the food, with which to build a living organism.

Each cell is made up of molecules. A molecule is the smallest quantity into which the mass of any substance can be divided and retain its characteristic properties.

Disassimilation means that the molecules of the cells disintegrate and are reduced to simpler and more stable elements; and at the same time there is a loss of energy.

The disintegration of molecules is attended by the loss of forced-heat or energy. This means the wearing-out of the cell; and the phenomenon is a manifestation of life, the same as the building-up. One is appropriating nourishment, the other is discarding worn-out material; and all the phenomenon is metabolism--nutrition or life.

It is well to note, in this connection, that life is the same, from the ameba found in the slime at the bottom of a pool of waste water, to the cell in the gray matter of a Websterian brain; from the lowest vegetable cell found at the mouth of the sewer, to the highest type of the most exquisite flower. All cell life is generically the same, differing or dividing into species.

The laws of nutrition are the same. The plant cell liberates force as does the animal cell, and both produce carbonic acid. The electron or carbon from the sun's rays, and the oxygen from the earth's atmosphere, meet in the cell and are united into carbonic acid, This phenomenon is not carried on in plant life to the extent that it is in animal life. The plant does not spend so much energy; assimilation predominates in plant life. The cells of the plant feed upon carbonic acid and water, which, under the influence of the sun's rays, unite into hydrate of carbon, furnishing vital force to animals. It was Herschel who first declared that the sun's rays are the source of all life.

In the study of cell life, four chief phenomena are observed; namely, a physical--that of taking in nourishment--absorbing--endosmosis; a chemical, consisting of organizing the material absorbed; disorganization; and, lastly, the throwing-out of the waste, which is called exosmosis.