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"The column had extended to about two thirds of the way toward the sea, and nearly connected itself with the basin, when a heavy shower of rain fell from the right of the arch, and shortly after another fell from the opposite side. This discharge appeared to have an effect on the water-spout, which now began to retire.

“The sea, on the contrary, was perceptibly more agitated, and for several minutes the basin continued to increase in size, although the column was considerably diminished (fig. 5).

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"In a few minutes more the column had entirely disappeared. The sea, however, still continued agitated, and did not subside for three minutes after all the disturbing causes from above had vanished. The phenomenon was unaccompanied by thunder or lightning, although the showers of rain which fell so suddenly seemed to be occasioned by some such disturbance."

M. Peltier has attempted to illustrate the electrical origin of these phenomena by producing them artificially. With this view he has represented the cloud in which the meteor originates by a globe of metal kept constantly charged with electricity by a machine. The inequalities of the cloud he represented by points raised on the surface of a globe. By means of the influence which this globe exercised upon water, vapors, and dust, he was able to produce a depression of the liquid, and the vortical or gyratory motion, and some other effects similar to those observed in the meteor.

All these effects disappeared when the globe was divested of points. In this case, instead of a depression, an elevation was produced; the vapors rose under the smooth ball, but showed little agitation. When the points were restored, the vapor was increased in more than a threefold proportion. The globules of vapor, being electrified at a distance by the points, were repelled in all directions, and made to whirl, more or less, according to the degree of the electric charge.

There are other electrical experiments made with other views, which M. Peltier brings to bear on the illustration of water-spouts.

A plate of copper, not insulated, being placed under a sphere, a little light ball is placed between them. When the sphere is electrified, the ball plays alternately upward and downward between the sphere and the plate; but if, instead of the ball, elongated or flat bodies be interposed, so as to present only a long and narrow strip of gold leaf, the alternate motion just described is transformed into a vortical motion, which ultimately becomes one of rapid ro

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bodies, oppositely electrified, are attracted and raised toward the cloud; when their electricity is neutralized they fall again upon the earth, where, being once more charged with electricity, they reascend, and so on. It is thus that an immense cloud of dust is formed under the cone. If the bodies are attached to the earth, like trees or buildings, they are instantaneously charged with an immense quantity of electricity. The earth, which is contiguous to them, partakes of this electricity, yields to the attraction of the cloud, and the trees, buildings, or other objects upon it, are torn up and transported afar. It is in this manner that bodies which are strongly attached to the earth are torn from it, while others in their immediate neighborhood are undisturbed. All these effects are subject to infinite variation, according to the conducting powers of the bodies, and of the parts of the earth to which they are attached.

If the great lightness of the clouds prevents them from falling sufficiently low to be in electrical communication with the ground, then the electricity will be discharged at a distance, attended by the flash of lightning and the roll of thunder. The electric tension will gradually diminish, rain will ensue, and the cloud will rise.

The sound which sometimes accompanies this phenomenon is attributed, by M. Peltier, to a number of small partial explosions, which take place between the cloud and ground. They are louder in the case of water-spouts which traverse the land, because of the imperfectness of the conductors presented to them; they lose their intensity over the sea because water is a better conductor.

Considering the progress of the air under the different attractions and repulsions to which it is submitted, and the contrary and unequal currents encountering different obstacles, M. Peltier endeavors to explain how the direct motion impressed on the air is changed into a gyratory motion more or less decided. It results from this, that the same meteor may present at different moments an example of direct and gyratory motion.

When the meteor is presented over water, its inductive action gives to the water near the surface an opposite electricity, and a consequent attraction ensues. If the contrary fluids do not unite by explosion, the surface of the water will swell upward at the several points of attraction, and the moment a discharge takes place, and the contrary fluids unite by explosion, this elevation subsides.

If, however, the electrified cloud is formed with points or prominences, which favor the escape of the electric fluid, the water becomes charged with the fluid descending from the cloud, and, being similarly electrified, is repelled by the cloud, and therefore depressed. Currents result from this in the water, which soon acquire a vortical motion.

On similar principles, M. Peltier explains the rapid disappearance of pools, or small collections of water, the entire mass being electrified by induction, and raised like trees and other objects.

The discharge of electricity through water may kill the fish contained in it; but the mere transmission of an electric current through the liquid without explosion will not have this effect, unless a considerable elevation of temperature takes place. An electric discharge passing near water, but not through it, may kill animals in it, by the effect of the lateral shock. By these principles, many of the observed effects of water-spouts are explained.

When by induction the electrical tension of the ground and objects upon it is elevated, the fluid with which it becomes charged will have a tendency to escape by all pointed conductors, and to issue upward toward the cloud. If the conductor be imperfect, an elevation of temperature will attend these upward currents, the effects of which will be apparent in the conductors by which

they escape. Trees, plants, and vegetables, conducting the electric fluid imperfectly by means of their sap, are dried up by this temperature; and wher the elevation takes place suddenly, the vapor into which the sap is converted splits the wood.

Such is a general outline of the theory of M. Peltier, by which the phenom ena attending water-spouts and whirlwinds are explained.

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