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Upon that part of the descriptior which relates to the mimic prester, Mr. Good observes as follows: “ Lucretius here alludes to meteors of a similar description, but not quite so tremendous in their effect: and is generally supposed to refer to the hurricane, or, as the Greeks termed it, EXvEQIA ; which is equally an electri. cal phænomenon, and may be regarded as a prester occurring on land, and consequently as an electric cloud filled with elastic air only, or other vapours received from the atmosphere, and not often with water. It is produced in the same manner as the sea. prester, has the same kind of elongated tube reaching towards the negatively electrified portion of the earth by which it is attracted, and is accompanied, previous to its bursting, by a similar tornado of external air. This elongated tube, as well as the substance of the cloud itself, in the time of Shakspeare, was supposed to have its film or fibres condensed and rendered firmer by the operation of the rays of the sun; but there is no necessity for such an idea :
-the dreadful spout Which shipmen do the hurricano call, Constriog'd in mass by the almighty sun.
TROILUS and CRESSIDA.
“ We may account for the phenomenon in this manner : that the thirsty cloud, in consequence of a more elevated position than ordinary in the atmosphere, at the time it commences its attraction with the water below, satiates and distends itself, by means of its proboscis, with absorbed air alone, prior to the actual contact of such proboscis with the hillock of rising water; so that, by the time this elongating spout extends to the attracted hillock, it is totally incapable of containing any thing farther."
Cavallo thinks electricity rather a consequence than a cause of water-spouts; and notices that they sometimes vanish and reappear.
Franklin, in his work on electricity, conceives a vacuum is made by the rotatory motion of the ascending air, as when water is run. ning through a tunnel, and that the water of the sea is thus raised. But it is justly observed by Dr. Young, that no such cause as this could do more than produce a slight rarefaction of the air, much less raise the water to above thirty or forty feet. At the same time the
* Vol.iii. p. 306.
force of the wind thus excited might carry up much water in de. tached drops, as it is really observed to exist in water-spouts. Dr. Young remarks, moreover, in another passage, that the phenomena of water-spouts, if not of electrical origin, appear to have some connexion with electrical causes. A water-spout generally consists of large drops, like a dense rain, much agitated, and descending or ascending with a spiral motion, at the same time that the whole spout is carried along horizontally, accompanied in general by a sound like that of the dashing of waves. Spouts are sometimes, although rarely, observed on shore, but generally in the neighbourhood of water. They are commonly largest above; sometimes two cones project, the one from a cloud, the other from the sea below it, to meet each other, the junction being accompanied by a flash of lightning: and when the whole spout has exhibited a luminous appearance, it has perhaps served to conduct etectricity slowly from the clouds to the earth. Some of these circumstances may be explained by consi. dering the spout as a whirlwind, carrying up drops of water, which it has separated from the surface of the waves; and the remainder may perhaps be deduced from the co-operation of electricity, al. ready existing in a neighbouring cloud.
Genuine Presters or Water-spouls.
1. Observed in the Mediterranean.
By Alexander Stuart,
August 27, 1701, being on the coast of Barbary, to the north. ward of the town of Bona, upwards of ten leagues distance at sea, about seven o'clock at night, soon after sunset, there appeared in
the N.E. which was directly up the gulf of Lyons from us, great a and continued flashes of lightning, one after another, with hardly
any intermission, and this, without thunder, it continued till the next morning ; the flashes of lightning sometimes representing the sudden appearance of a star, and at other times of a flaming sword, and again of a silver cord stretched along the clouds, or as the irre. gular rents of a phial from top to bottom. About eight next morn.
ing we had thundering, with a continuation of lightning of the kind and appearance as before, al from the N. E. or nearly so.
A bout nine the same morning, there fell down from the clouds, which looked black, lowering, and as it were heavy with rain, in the N.E. three water-spouts; that in the middle, being the greatest, seemed as large as the mast of a ship, and I judged it to be at least a league and a half distant from us ; so that in itself it was doubt. less larger than three masts. The other two were not half the size. All of them were black, like the cloud from whence they fell; and smooth, without any knot or irregularity; only at first falling, some fell perpendicularly down, and some obliquely, and all of them smaller at the lower end than above, representing a sword; some. times also one of them would bend, and become straight again, and also sometimes became smaller, and again increase its bulk; some. times it would disappear, and immediately fall down again; at other times it became extenuated to the smallness of a rope, and again became gross as before.
There was always a great boiling and flying up of the sea, as in a jet d'eau, or water.work; or this rising of the water had the ap. pearance of a chimney smoking in a calm day. Some yards above the surface of the sea, the water stood like a pillar, and then spread itself, and was dissipated like smoke: and the sword.like spout from the clouds either came down to the very middle of this pillar, as if it had been joined with it, as the largest pillar, which fell per. pendicularly down, always did from the beginning to the end; or else it pointed to this column of water, at some distance, either in a perpendicular or oblique line, as did the two other lesser ones. There were three or four spouts more, which appeared at the same time in the same quarter of the heavens; but not like the three former, either for bulk or duration : these last appeared and disap. peared several times, during the continuance of these three afore. said.
It was hardly distinguishable whether the sword-like spont fell first down from the cloud, or the pillar of water rose first from the sea; both appearing opposite to each other all of a sudron only observed of one of them, that the water boiled up from the sea to a great height, without the last appearance of a spout pointing to it, either perpendicularly or obliquely; and here the water of the sea never came together in the form of a pillar, but rose up scat.