It is important that we should now review these conditions of electrical force in connexion with the great physical phenomena of nature.
It is sufficiently evident, from the results which have been examined, that all matter, whatever may be its form or condition, is for ever under the operation of the physical forces, in a state of disturbance. From the centre to the surface all is in an active condition: a state of mutation prevails with every created thing; and science clearly shows that influences are constantly in action which prevent the possibility of absolute repose.
Under the excitement of the several agencies of the solar beams, motion is given to all bodies by the circulation of heat, and a full flow of electricity is sent around the earth to perform its wondrous works. The solar influences, which regulate, and possibly determine, every physical force with which we are acquainted, are active in effecting an actual change of state in matter. The sunbeam of the morning falls on the solid earth, and its influence is felt to the very centre. The mountain-top catches the first ray of light, and its base, still wrapt in mists and darkness, is disturbed by the irradiating power. The crystalline gems, hidden in the darkness of the solid rock, are dependent, for that form which makes them valued by the proud and gay, on the influence of those radiations which they are one day to refract in beauty. The metals locked in the chasms of the rifted rocks are, for all their physical peculiarities, as dependent on solar influence as is the flower which lifts its head to the morning sun, or the bird which sings “at heaven’s high gate.”
Let us, then, examine how far electricity, as distinguished from the other powers, acts in producing any of these effects.
We find electricity in the atmosphere, which the electrical kite of Dr. Franklin proved to be identical with that principle produced by the friction of glass. In the grandeur and terror of a thunderstorm, many see nothing but manifestations of Almighty wrath. When the volleys of the bursting cloud are piercing the disturbed air, and the thunders of the discharge are pealing their dreadful notes above our heads, the chemical combinations of the noxious exhalations arising from the putrefying animal and vegetable masses of this earth are effected, elements fitted for the purposes of health and vegetation are formed, and brought to the ground in the heavy rains which usually follow these storms. Science has taught man this--has shown him that the “partial evil” arising from the “winged bolt” is a “universal good;” and, more than this, it has armed him with the means of protecting his life and property from the influence of lightnings. So that, like Ajax, he can defy the storm. By metallic rods, carried up a chimney, a tower, or a mast, we may form a channel through which the whole of the electricity of the most terrific thunder-cloud may be carried harmlessly into the earth or the sea; and it is pleasing to observe that at length prejudice has been overcome, and “conductors” are generally attached to high buildings, and to most of the ships of our navy.[151] It was discovered that the devastating hailstorms of the south of France and Switzerland, so destructive to the vineyards and crops, were accompanied by evidences of great electrical excitation, and it was proposed to discharge the electricity from the air by means of pointed metallic rods. These have been adopted, and, it is said, with real advantage--each rod protecting an area of one hundred yards. Thus it is that science ministers to our service; and how much more pleasing is it to contemplate the lightning, with the philosopher, as an agent destroying the elements of pestilence, and restoring the healthfulness of the air we breathe, than with the romancer, to see in it only the dreaded aspect of a demon of destruction.