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be quietly dissipated, or attracted to the ocean; but, if it be stronger and more viscous, it will continue to stretch without bursting; and, like every other elastic substance, the more it stretches, the narrower will be the projected tube. Such, to the mariner, is the actual ap perance of the column of the water-spout, precisely resembling a speaking trumpet, with its base or broader part uppermost. When the mouth of this projected tube touches the rising hillock of water, if the attraction of the negatively electrified ocean be superior, the electric aura, we may naturally suppose, will be drawn downwards, and the empty cloud be totally dissipated; but, as will generally occur in the case of a positive force applied to a negative, if the attraction of the electric cloud prove victorious, it will continue to suck up the rising hillock of water till it is altogether sated, and can hold no more. At this time the cloud must necessarily burst from its own weight and distention, and in proportion to its size, and the deluge of water and electricity it discharges, will be the mischief produced. It is said that it may occasionally be rent, at a distance, by making a violent noise on board the ship in which it is perceived by files, saws, or other discordant instruments; and, certainly, whatever will tend to agitate the air in any considerable degree, affords some prospect of breaking the cloudy film, and thus dispersing the meteor; but the more ordinary method of shooting at it from guns of a large calibre, gives a much stronger, and, indeed, almost certain chance of success; for no mechanical power can agitate the surrounding atmosphere by any means se forcibly as the report of a large cannon; and, if it be loaded with ball, it will give a double prospect of discharging the contents of this tremendous spectacle.'
Upon that part of the description which relates to the mimic prester, Dr. 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, Ekvepia; which is equally an electrical phenomenon, and may be regarded as a prester occurring on land, and consequently as an electric cloud filled with elastic air only, or other vapors 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 :
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 supposes that electricity is rather a consequence than a cause of water-spouts; and notices that they sometimes vanish and reappear. Dr. Franklin conceived that a vacuum is made by the rotatory motion of the ascending air, as when water is running 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 rarefication of the air, much less raise the water to above thirty or forty feet. At the same time the force of the wind thus excited might carry up much water in detached 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 electricity slowly from the clouds to the earth. Some of these circumstances may be explained by considering 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, already existing in a neighbouring cloud.
One of the best accounts of the appearance of the genuine prester is given by Mr. Maxwell in the Edinhurgh Philosophical Journal.
During several voyages to Congo, he frequently witnessed this interesting phenomenon ; and in a drawing in his Journal, from which fig. 1 of our plate METEOROLOGY is copied after the Edinburgh Philosophical Journal, he has represented the different states of a water-spout, as they most commonly occur.
"At their first formation they appear,' he says, as at A, where the black cloud drops from a level surface into a conical form, before the disturbance at the surface of the sea, as shown at D, is observed. The effect produced at D is like that of a smoking furnace. The black conical cloud now continues to descend, as shown at B, till it almost reaches the surface of the sea, and the smoke-like appearance rises higher and higher till it forms a union with the cloud from which the spout appears to be suspended. In this si
tuation it is said to put on its most terrific appearance to the mariners who have the misfortune to be in its neighbourhood. When the spout begins to disperse it assumes the appearance shown at C. The black cloud generally draws itself up in a ragged form, but leaves a thin transparent tube C E, which reaches to the water where the smoke-like commotion still prevails. Mr. Maxwell observed at this time in the upper part of the tube a very curious motion.'
This fact, of the existence of a transparent tube, confirms Mr. Alexander Stewart's description in the Philosophical Transactions, of the water-spouts which he saw in the Mediterranean in 1701. It was observable of all of them,' says he, but chiefly of the large pillar, that towards the end it began to appear like a hollow canal, only black in the borders, but white in the middle; and, though at first it was altogether black and opaque, yet one could very distinctly perceive the sea-water to fly up along the middle of this canal as smoke does up a chimney, and that with great swiftness, and a very perceptible motion; and then, soon after, the spout or canal burst in the middle, and disappeared by little and little; the boiling up and pillar-like form of the sea water continuing always the last, even for some considerable time after the spout disappeared, and perhaps till the spout appeared again, or reformed itself, which it commonly did in the same place as before, breaking and forming itself again several times in a quarter or half an hour.' --Philosophical Transactions 1702, p. 1077.
We copy the following from the Journal of the Royal Institution.
Extract of a letter from William Ricketts, esq. Captain in the Royal Navy, to the Right Hon. Sir Joseph Banks, Bart. &c. &c.
In the month of July, 1800, captain Ricketts was suddenly called on deck, on account of the rapid approach of a water-spout among the Lipari Islands; it had the appearance of a viscid fluid, tapering in its descent, proceeding from the cloud to join the sea; it moved at the rate of about two miles an hour, with a loud sound of rain; it passed the stern of the ship, and wetted the after-part of the mainsail; hence captain Ricketts concluded that water-spouts were not continuous columns of water; and subsequent observations confirmed the opinion. See plate METEOROLOGY, fig. 2.
In November, 1801, about twenty miles from Trieste, a water-spout was seen eight miles to the southward; round its lower extremity was a mist, about twelve feet high, nearly of the form of an Ionian capital, with very large volutes, the spout resting obliquely on its crown. At some distance from this spout the sea began to be agitated, and a mist rose to the height of about four feet: then a projection descended from the black cloud which was impending, and met the ascending mist about twenty feet above the sea; the last ten yards of the distance were described with a very great rapidity. A cloud of a light color appeared to ascend in this spout like quicksilver in a glass tube. The first spout then snapped at about one-third of its height, the inferior part
subsiding gradually, and the superior curling upwards.
Several other projections from the cloud appeared, with corresponding agitations of the water below, but not always in spouts vertically under them: seven spouts in all were formed; two other projections were re-absorbed. Some of the spouts were not only oblique but curved: the ascending cloud moved most rapidly in those which were vertical; they lasted from three to five minutes, and their dissipation was attended by no fall of rain. For some days before, the weather had been very rainy with a south-easterly wind; but no rain had fallen on the day of observation.
The mimic or false prester, with little or no water, is a curious vagary of nature. On the 15th of August, 1617, there was observed by the Rev. Abraham De la Pryme, F. R. S., about two o'clock in the afternoon, a water-spout in the air, at Hatfield, in Yorkshire. It was about a mile off, coming directly to the place where I was,' says this gentleman, upon which I took my perspective glasses, and made the best observations on it I could.
'The season was very dry, the weather extremely hot, the air very cloudy, and the wind pretty strong, and what was remarkable blowing out of several quarters at the same time, and filling the air with thick and black clouds, in layers; this blowing of the wind soon created a great vortex, gyration, and whirling among the clouds, the centre of which now and then dropt down in the shape of a thick long black tube, commonly called a spout; in which I could distinctly see a motion, like that of a screw, continually drawing upwards, and screwing up as it were whatever it touched. In its progress it moved slowly over a hedge row and grove of young trees, which it made bend like hazel wands, in a circular motion; then, advancing forward to a large barn, in a moment it plucked off all the thatch, and filled the whole air with it. Coming to a very large oak tree, it made it bend like the former, and broke off one of its strongest branches, and, twisting it about, flung it to a very considerable distance off. Then coming near the place where I stood, within 300 yards of me, I beheld with great satisfaction this extraordinary phenomenon, and found that it proceeded from à gyration of the clouds, by contrary winds meeting in a point or centre; and, where the greatest condensation and gravitation was, falling down into a large pipe or tube, somewhat like the cochlea Archimedis; and which, in its working or whirling motion, either sucks up water, or destroys ships, &c. Having proceeded about a quarter of a mile farther, it was dissolved by the prevalency of the wind from the east.' Philosophical Transactions 1702.
May the 5th, 1752, a similar phenomenon appeared about seven in the evening, in Deeping-Fen, which, from its effects, seemed to be a water-spout, broken from the clouds. A watery substance, as it seemed, was seen moving on the surface of the earth and water, in Deeping-Fen. It passed along with such violence and rapidity, that it carried every thing before it, such as grass, straw, and stubble; and, in going over the coun
try bank, it raised the dust to a great height; and when it arrived in the Wash, in the midst of the water, and just over against where Mr. R. lived, it stood still for some minutes. This watery substance spouted out water from its own surface to a considerable height, and with a terrible noise. On its second route it proceeded in a side line into a river, breaking in its passage a fishing net, and there moved along, till it came to the church, where it again stood a little while, and then made its next passage through the space between the church and the parsonage-house, towards Weston Hills and Moulton Chapel. In its way to these places it tore up a field of turnips, broke a gate off its hinges, and another into pieces. Those who saw it evaporate, affirm it ascended into the clouds in a long spearing vapor, and at last ended in a fiery stream. There was a mist like smoke frequently round it. Three more were seen at the same time in different places. Id. 1751.
We subjoin the following as the most modern and amongst the most able accounts of the waterspout from Dr. Brewster's Journal. It is part of a letter from captain Napier, R. N., to that gentleman, dated 17th July 1821. 'I take the liberty of offering you the following observations, with the remarks made at the time, when the facts and appearances exhibited by this extraordinary phenomenon were deeply impressed upon my mind. On the 6th of September 1814, in lat. 30° 47′ N., and long. per chronometer 62° 40′ W., at 1h. 30m. P. M., the wind being variable between W.N.W. and N. N. E., the ship steering south-east, an extraordinary sort of whirlwind was observed to form about three cables length from the starboard bow of H. M. S. Erne. It carried the water up along with it in a cylindrical form, in diameter to appearance like that of a water-butt, gradually rising in height, increasing in bulk, advancing in a southerly direction, and, when at the distance of a mile from the ship, it continued stationary for several minutes, boiling, and foaming at the base, discharging an immense column of water, with a rushing or hissing noise, into the overhanging clouds; turning itself with a quick spiral motion, constantly bending and. straightening, according as it was affected by the variable winds which now prevailed alternately from all points of the compass. It next returned to the northward in direct opposition to the then prevailing wind, and right upon the ship's starboard beam, whose course was altered to east, in hopes of letting it pass a-stern. Its approach however was so rapid, that we were obliged to resort to the usual expedient of a broadside, for the purpose of averting any danger that might be apprehended, when, after firing several shots, and one, in particular, having passed right through it at the distance of one-third from its base, it appeared for a minute as if cut horizontally in two parts, the divisions waving to and fro in different directions, as agitated by opposite winds, till they again joined for a time, and at last dissipated in an immense dark cloud or shower of rain. The near edge showered in large heavy drops on the ship's deck, until the cloud was quite exhausted.
At the time of its being separated by the
effect of the shot, or more probably by the agitation occasioned in the air by the discharge of several guns, its base was considerably within half a mile of the ship, covering a portion of the surface of the water, at least half a furlong, or even 300 feet in diameter, from one extreme circumference of ebullition to the other, and the neck of the cloud into which it discharged itself appeared to have an altitude of 40° of the quadrant, while the cloud itself extended over-head, and all round to a very considerable distance. Allowing, then, from the ship, a base of a little more than one-third of a nautical mile, say 2050 feet, and an angle of 40° to the top of the neck, we shall then have, for the perpendicular height of the spout, about 1720 feet, or very nearly one-third of a statute mile. A little before it burst, two other water-spouts, of an inferior size, were observed to the southward, but their continuance was of short duration. When danger was no longer to be apprehended, I observed the barometer, and found it at 30 inches, with the surface of the mercury very convex, an appearance which it had not assumed when at the same height at noon, about two hours before; the thermometer stood at 82°, having risen 10 since that time.
'During the continuance of the water-spout, and the subsequent rain, which might be a little more than half an hour, the wind blew from all points of the compass at different times, generally shifting at opposite points, never stronger than a fresh breeze for a moment, but in most instances quite light. It was unattended with any thunder or lightning, and the water that fell from the cloud, and was caught in the foot of the driver, was perfectly fresh.
'Having witnessed this extraordinary phenomenon, I endeavored to ascertain its cause, taking for granted the following axioms:-1. That water in a vacuum rises only to the height of thirty-two feet,' or, in other words, 'that a column of water thirty-two feet high is equal in weight to a colunin of the atmosphere of the same base.' 2. 'That a column of mercury twenty-nine inches high, in vacuo, is equal to the same. 3. That heat rarifies the air and causes a vacuum.' 4. 'That when, the lower atmosphere is so much rarified as to become lighter than the impending clouds, then these clouds or vapors fall and disperse on the surface of the earth in the shape of rain or moisture.' 5. "That, when the clouds descend, the mercury in the barometer also descends, and that when the vapors rise through the lower atmospheres, becoming again more dense than the vapors themselves, the mercury in the barometer rises also.' With these data, were next noted the various phenomena, as observed to be connected with the water-spout itself.
'1. Low, heavy, black clouds were seen to the southward at noon, the barometer standing at 30 inches, and the thermometer at 81°, in a constant current of cool air; the atmosphere, in general, becoming hazy, even thick in some places, close and very hot,-the wind variable and attended with occasional drops of rain. A whirlwind next taking place, drawing the water up with it, apparently in a state like vapor or steam, advancing in a southerly direction to the above
mentioned dark impending clouds, increasing also in height and bulk, with a quick spiral motion, till it came in contact with the end of a cloud which rather drooped to meet it; then discharging great quantities of water, not in a solid bulk, but in short unconnected streams or streaks as it were, attended with a rushing or hissing noise. 2. That after some time it returned with considerable velocity to the northward, in opposition to the wind prevailing at the ship, the water at the base boiling with a white foam, part projecting outwards to a certain circumference, and part arising in thick dark vapors, which gradually arranged themselves into thin streaks, as they gained in ascent towards the clouds, till the whole was dispersed by bursting into a heavy shower. 3. That the clouds descended, or came gradually nearer to the surface of the sea, before they were perfectly saturated, previous to bursting. 4. That these clouds extended in large dark masses over a great part of the western hemisphere, and were quite thick and dark over-head. 5. That the water-spout, at the base, covered, in diameter, about half a furlong of water; and in its most slender part, about two-thirds upwards, it was to appearance about six feet in diameter; and that, in height, it might be estimated at 1700 feet: and, lastly, that during the operation of these extraordinary phenomena in the atmosphere, the mercury in the barometer did only become more convex than before, with the thermometer rising 1°.
"In proceeding to examine the subject, we shall suppose that the water rose from the sea in vacuo, or rather in a cylindrical space approximating to that of a vacuum, and that it was caused so to rise, in part, by the pressure of the atmosphere circumscribing the base of the said vacuum. Having allowed so much, we can go no further without violating the well-known law, that 'water cannot rise in vacuo' above thirty-two feet; admitting, therefore, that it was even assisted to that small height, we shall have availed ourselves of the theory, as far as truth or reason can justify. If we say that water is drawn upwards by the suction of a cloud, as proposed to be exemplified by Mr. Oliver with a quill over a glass of water, we shall then begin to establish the theory of suction,' perfectly irreconcileable, also, with the equally well-known fact of the gravity of the atmosphere. Besides, the force of Mr. Oliver's lungs, over a glass of water, can bear no analogy to that of a cloud overhanging the surface of the It appears also strange to talk of an empty cloud, or a half exhausted cloud, for clouds are not aerial bags, as some would have them to be, but vapors overhanging the earth at different heights from it, according to the proportion of humidity or density contained in themselves, and which, when, by reason of their greater weight, they fall within the sphere of the earth's attraction, begin to discharge themselves in rain, till, being reduced in size and density, if not totally consumed, they naturally rise above the sphere of attraction, and, regaining the higher parts of the atmosphere, again attract each other, and repeat such operations to the end of time.
'Setting aside, then, the theory of suction, and the idea that the water-spout could rise in a body
to the clouds, by the pressure of the circumambient atmosphere alone, we shall have the following probabilities to bring us to a more rational conclusion. 1st, That many opposite currents of wind, all pointing towards a certain centre, and coming in contact with each other with unequal forces, cause a rotatory motion or current of themselves round a central space, which, not partaking of an equal or its former pressure, naturally becomes rarified by the existing heat, to such an extent, that it speedily acquires a state in a great degree approximating to that of a vacuum. 2dly, This continued rotatory motion of the air forms that which is usually denominated a whirlwind; and the pressure of the external atmosphere at the base, forcing the water to a reasonable height up the rarified space within, it is then carried upwards by the mechanical action of the wind in light and unconnected streaks. The space at the bottom, now becoming void, is regularly replenished by the pressure from without, till the whole spout is in due time thus perfectly completed.
The water having now arrived at the region of the clouds, it is naturally attracted, diffused and connected with and among them, increasing in density and extent, till the lower atmosphere becoming now lighter than the clouds above, these enormous masses gradually settling downwards, distend, burst and dissipate in rain. That the mercury in the barometer did not fall with the rain, but, on the contrary, became considerably more convex, was visible from observation and may be accounted for in the following manner:-That during the whole operation of the water-spout, which continued not more than thirty minutes, the commencement was too sudden, and the duration too short, to cause any change indicative of what actually took place; and that this convexity only prognosticated what would have taken place, had there been no water-spout at all, and what actually did happen afterwards, viz. a very clear atmosphere and hot sultry weather.
Although this phenomenon was rather terrific in appearance, yet I am not inclined to think it would have been attended with any serious calamity to the ship, had even the whole quantity fallen on board, allowing the loftier sails to have been taken in, the hatches battened down, and scuppers open. The cylinder or spout, coming in contact with the masts and rigging, would naturally be destroyed; and, the air rushing in instantaneously to restore the equilibrium, the torrent would be thus checked in its fall to the mere weight or force of a tropical descent. I have heard many reports of ravages committed by these aqueous meteors, but never yet met a person who had actually witnessed or experienced any such distressing effects. Upon comparing the present account with that of Mr. Maxwell's, illustrated by a very striking representation, it appears that, when completed, the two spouts are almost perfectly alike, but originally had derived their first formation from different sources. The cause of the whirlwind must be the same in