The Poetry of Science; or, Studies of the Physical Phenomena of Nature

by Robert Hunt

Has poetry a nobler theme than this? Agencies are seen like winged spirits of infinite power, each one working in its own peculiar way, and all to a common end,—to produce, under the guidance of omnipotent rule, the waters of the rivers and the seas. As the great ocean mirrors the bright heaven which overspreads it, and reflects back the sunlight and the sheen of the midnight stars in grandeur and loveliness; so every drop of water, viewed with the knowledge which science has given to us, sends back to the mind reflections of yet distant truths which, rightly followed, will lead us upwards and onwards in the tract of higher intelligences,—

“To the abodes where the eternals are.”

In the discoveries connected with electricity, we have results of a more tangible character than are as yet connected with the other physical forces; and it does appear that this science has advanced our knowledge of nature and of the mysteries of creation far more extensively than any other department of purely experimental inquiry.

The phenomena of electro-chemical action are so strange that we must return for a moment to the consideration of the decomposition of water, and the appearance of hydrogen at one pole, and of oxygen at the other. It appears that some confusion of our ideas has arisen from the views which have been received of the atomic constitution of bodies. We have been accustomed to regard water,—to take that body as an example of all,—as a compound of two gases, hydrogen and oxygen; an equivalent, or one atom of the first, united to an equivalent or one atom of the last, forming one atom of water. This atom of water we regard as infinitely small; consequently a drop of water is made up of many hundreds of these combined atoms, and a pint of water of not less than 10,000 drops. Now, if this pint of water is connected with the wires of a galvanic battery, although their extremities may be some inches apart, for every atom of oxygen liberated at one pole, an atom of hydrogen is set free at the other. It has been thought that an atom has undergone decomposition at one point, its oxygen being torn from it, and then there has arisen the difficulty of sending the atom of hydrogen through all the combined atoms of water across to the other pole. A series of decompositions and recompositions have been supposed to take place, and the communication of effects from particle to particle.

An attracting power for one class of bodies has been found in one pole, which is repellent to another class; and the reverse order has been detected at the opposite pole of a galvanic arrangement.[144] That is, the wire which carries the current from an excited zinc plate has a relation to all bodies, which is directly opposite to that which is exhibited by the wire conveying the current from, or completing the circuit with, the copper plate. The one, for instance, collects and carries acids and the like, the other the metallic bases. At the extremity of one galvanic wire, placed into a drop of water, oxygen is always liberated; and at the end of the other, necessary to complete the circuit with the battery, hydrogen is set free.

It appears necessary, to a clear understanding of what takes place in this experiment, that we should regard each mass, howsoever large, as the representative of a single atom. Nor is this difficult, as the following illustration will show.

Let us take one particle of common salt (chloride of sodium) weighing less than a grain, and put it into a hundred thousand grains of distilled water. In a few minutes the salt has diffused itself through the whole of the fluid, and in every drop we can detect chlorine and soda. We cannot believe that this grain of salt has split itself up into a hundred thousand parts; we conceive rather that the phenomenon of solution is one of diffusion. One infinitely elastic body has interpenetrated with another.

Instead of an experiment with a pint of water, let us take our stand on Dover heights, and, with a gigantic battery at our command, place one wire into the ocean on our own shores, and convey the other through the air across the channel, and let its extremity dip into the sea off Calais pier—the experiment is a practicable one—we have now an electrical circuit of which the British channel forms a part, and the result will be exactly the same as that which we may observe in a watch-glass with a drop of water.