Joseph Smith as Scientist: A Contribution to Mormon Philosophy - John Andreas Widtsoe

[Sidenote: The molecules are beyond man's direct senses.]

An exposition of the fundamental conception of chemical science will illustrate the nature of scientific faith. A fragment of almost any substance may easily be divided into two or three pieces by a stroke of a hammer. Each of the pieces may be broken into smaller pieces and this process of division continued until the powder is as fine as dust. Still, each particle of the dust may be divided again and again, if we only have instruments fine enough to continue the process. A question which philosophy asked itself near its beginning was: Is it possible to keep on dividing the dust particles forever, or is there a particle so small that it can not be divided again? Neither science nor abstract philosophy has yet been able to answer this question fully. However, science has learned that if such a process of division occurs, in course of time a particle will be obtained which is so small that if it is divided or broken, the fragments will no longer be of the same nature as the original substance. These smallest particles in which the properties of the original substance inhere, are known as molecules. Thus a molecule of sugar, when broken, falls into the elements carbon, hydrogen and oxygen; of salt, into sodium and chlorine and of water into hydrogen and oxygen.

The size of such a molecule can not be comprehended by the human mind; its smallness seems infinite. The mortal eye, though aided by the most powerful miscroscopes of modern days could not distinguish a sugar molecule or even a pile of thousands of them; placed on the tongue, there would be no sensation of sweetness; though it were hurled against our body with the velocity of lightning we should not feel the impact. To all our senses, the molecule is wholly unknown and no doubt shall remain so while the earth is as it is. Yet, no fact is better established than the existence of the realities that we interpret as molecules. Their relative weights and other properties have been securely determined. The existence of such a particle is as certain as is the existence of the sun in the high heavens.

[Sidenote: Science teaches the composition of the directly unknowable molecules.]

Not only does science teach the existence of molecules; it looks within them and reveals their composition. For instance, a molecule of the sugar known as glucose, and used by candy makers, is made up of six particles of the element carbon, twelve of the element hydrogen and six of the element oxygen. The particles of carbon in the glucose molecule are so small that if one were divided it would no longer be carbon; the same with the particles of hydrogen and oxygen: if divided they would change into something else—into what is not yet known to man. These smallest particles are called atoms of the elements charcoal, hydrogen and oxygen. If instead of an atom of carbon, hydrogen and oxygen, we write C, H, O, the composition of a molecule of glucose would be written C_{6}H_{12}O_{6}. These are also indisputable facts of science. If the molecules are far beyond the range of our senses, the atoms are of course much further removed from the known world.

[Sidenote: Science teaches the arrangements of the atoms within the molecules.]

But the chemist does not stop here. He is able to state accurately how the invisible, unsensed atoms are arranged within the unknowable molecule. In nature are found several glucose-like sugars, the molecules of which contain the same numbers of carbon, hydrogen and oxygen atoms. The varying properties of these sugars have been found to result from the different arrangements of the atoms within the molecules. The structure of the molecules of three of the most common sugars are as follows:

[Footnote A: Dextrose and laevulose combine to form ordinary cane or beet sugar. Dextrose and galactose combine to form the sugar found in milk.]

Referring to the above diagrams it will be observed that although each arrangement contains the same number of atoms, yet, because of the difference in arrangement, they are far from being identical. In fact, the difference in the properties of the sugars may be referred to the arrangement of the atoms in the molecules. This truth is one of the most splendid achievements of modern science. All the facts, here briefly outlined, are included in the atomic hypothesis, which is the foundation of the modern science of chemistry.