These circumstances, among others, led Dr. Gibbes to conclude that when hydrogen gas is produced by the affusion of water on red-hot metal, and the metal is at the same time oxydated, a decomposition of fire rather than of water has taken place; that the hot metal has parted with negative electricity, which, uniting with a small proportion of the water, has formed hydrogen gas; that a greater proportion of the water has united with the positive electricity, and entered, as oxygen gas, into combination with the metal. When the two gases are inflamed together, the spark attracts to itself, in due proportions, the two electricities contained in the two gases, which unite with explosion, and produce fire. The water with which they were before combined is of course deposited.
The reason why inflammable substances burn in oxygen gas, and not in hydrogen, Dr. Gibbes supposes to be, that negative electricity greatly prevails in all inflammable substances. Neither of the gases can be inflamed separately, because fire depends on the union of the two electricities; and such union cannot be effected unless both are present in due proportion.
Dr. Gibbes supposes that the further illustration of the effects of the two electricities, as chemical agents, will set aside some of the leading doctrines of the Lavoisierian theory, and afford an easy solution of certain phenomena which that theory cannot explain.
Æpinus’ Theory of Electricity.
Mr. Æpinus, of the imperial academy of Petersburgh, has attempted to class the phenomena of electricity and magnetism in a mathematical method. In the course of his works he gives some views of the subject which are new and highly ingenious, and as some good judges suppose, calculated to surmount many difficulties, and to answer many questions, which occur in considering the Franklinian theory. The leading principles of his plan are comprehended in the following propositions.
1. Its particles repel each other, with a force decreasing as the squares of the distances increase.
2. Its particles attract the particles of some ingredients in all other bodies, with a force decreasing according to the same law, with an increase of distance; and that this attraction is mutual.
3. The electric fluid is dispersed in the pores of other bodies, and moves with various degrees of facility through the pores of different kinds of matter. In those bodies which we call non-electrics, such as water or metals, it moves without any perceivable obstruction; but in glass, resin, and all bodies called electrics, it moves with very great difficulty, or is altogether immoveable.
4. The phenomena of electricity are of two kinds: 1. Such as arise from the actual motion of the fluid, from a body containing more, to one containing less of it. 2. Such as do not immediately arise from this transference, but are instances of its attraction and repulsion.—
These principles are applied at great length, and with a pleasing degree of precision, by the ingenious theorist, to the Leyden phial, and to the various phenomena of electric attraction and repulsion. It will be readily seen that Æpinus adopts, in substance, the theory of Franklin, of which, in some particulars, he presents new and more satisfactory views than the American philosopher. In the sixty first volume of the Philosophical Transactions, there is a dissertation by the Hon. Mr. Cavendish on this subject, which he considers as an extension and more accurate application of Æpinus’s theory.