“Sayings, Wise and Otherwise,” (also in the “The Sayings of Dr. Bushwhacker and Other Wise Men”) by Frederic S. Cozzens; American Book Exchange, New York; 1880; pp. 136-139.
“First, let me talk with this philosopher. What is the cause of thunder?” — King Lear, Act III, Scene Fifth.
“A SERIES of observations, and a single experiment, would throw some light upon this important question. Take, for instance, a summer afternoon when the air is close and sultry, and the atmosphere rarefied, when respiration is laborious, and no wind stirring among the leaves. But, on the distant horizon, there are indications of vapor; not rolling clouds, but thin exhalations from the earth, drawn up by the heat of the sun. Suddenly this humid veil is illuminated by flashes, and people call it heat lightning, summer lightning, sheet lightning. I wish particularly to direct attention to the fact, that this exhibition of electricity is not often accompanied with other phenomena peculiar to thunder storms. No rain follows the flash, nor is any report heard; and, furthermore, these illuminated vapors are always much elevated.
It is idle to say that on account of distance from the earth the report is not audible; for few persons, familiar with mountain heights, can fail to remember that some 137 time or other they were in the midst of such an atmosphere, when the lightning appeared to surround them, apparently within a few feet of them, flashing on every side, yet without rain or detonation. In this condition the atmosphere is said to be highly charged with electricity. But surely we cannot accept this as equivalent to the same meaning applied to a Leyden jar, fresh from contact with the knob of the electric machine. Indeed, is not the contrary very possible? Would not the data show that, in such a condition the atmosphere, instead of being highly charged, had not its usual percentage of electric stimulus? Experiments with the electrometer might prove this supposition to be correct, and, on the other hand, they might prove it to be incorrect. But one thing cannot be disproved nor denied — that air, highly rarefied by heat, and humid, is air, plus water; and also that in this condition air is susceptible of being silently illuminated by electricity. This point being settled, we will proceed to the next — which is, “What is the cause of Thunder?”
The learned, down to the latest moment of going to press, have advanced no further than this, that “thunder is a noise produced by THE EXPLOSION OF LIGHTNING, or by the passage of lightning from one cloud to another! or from a cloud to the ground.” Whoever has read the celebrated treatise of John Conrad Francis de Hatzfield upon the subject, will find a far more plausible theory advanced by that sagacious philosopher, and quite as 138 amusing as the modern idea, that the sound of thunder is analogous to the snap produced by holding the knuckle of one’s forefinger to the brass bulb of an electrical machine! — an explanation that has never satisfied any reasonable mind. Let us see if there be not a rational solution of the mystery.
The phenomena of thunder storms are: first, heavy clouds; then lightning; then the report, and then a fall of rain! Now, let us trace the consequence to its source. The rain is produced by two causes, either sudden condensation of watery vapors or clouds, by colder temperature, or the formation of water by the action of the electric fluid. The first explains itself; the latter is linked with the subject of this paper. Let us, therefore, confine ourselves to that rain only which follows the thunder. Rain water is composed of two elements, oxygen and hydrogen. Hydrogen is a combustible gas, and oxygen supports combustion. A stream of pure hydrogen, ejected from a pipe into pure oxygen, burns brightly in perfect silence. But, mixed with oxygen, it explodes upon taking fire; just as a young man, having his own fortune to make, goes quietly to work until he gets a partner with a tremendous capital. The relative aspects of silent lightning and noisy lightning may be compared by a simple apparatus sold at any chemists; it is a tin lamp filled with inflammatory gas. So long as the gas is allowed to burn in small quantities it is taciturn, but, exposed to a larger mixture of oxygen, it goes off with a 139 loud report. This is a lamp that any spark of electricity can ignite. And then again the product of the flame is water! The union of hydrogen and oxygen is water. What meteoric phenomenon is so simple as this, that thunder is caused by the electric spark uniting with rarefied air plus oxygen, and rarefied vapor plus hydrogen, detonating, recompounding, and forming rain!