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this fearful phenomenon in the following verses of his Botanic Garden.
“ Now o'er their head the whizzing whirlwinds breathe,
THE PRESTER, OR WATER-SPOUT.
MANY of the preceding meteors, or atmospherical phænomena, and especially those described under the name of hurricanes, tor. nadoes, and whirlwinds, are connected, as we have occasionally hinted at already, with the electric state of the atmosphere. We now advance to a meteor that is still more decidedly of this com. pound character, and which seems to be a combination of wind, aqueous vapour, and electric fluid.
The existence of this singular and most active phænomenon has been long known to the philosophical world: and by the Greeks, and after them by the Romans, was described under the name of PRESTER, which imports a fiery fluid of some kind or other. Gassendi, indeed, contended that the Prester of the ancients was a mere tornado or whirlwind, but this was before the nature, or even the existence, of electricity, as a definite power, had been accurately ascertained, however suspected formerly: and we have already observed that Mr. Capper, in the preceding chapter, has been betrayed by so learned a guide into the same error, and has regarded the Prester as a whirlwind or tornado of a peculiar species. To prove this error nothing more is ne. cessary than to quote the description of the Prester, as given by Lucretius, and to follow up the quotation, with the explanation of his learned translator : by which it will abundantly appear, that the Prester, like the spout of the present day, was regarded as both a sea and land meteor, or in other words as filled with water, and without water; the term being more properly applied to the former, and the latter being correctly regarded and called a mimic, or imitative Prester, in reality the fiery wirlwind or hurricane which we have already noticed in one or two of the articles of the last section of the preceding chapter, or a phænomenon most closely allied to it. The passage we advert to is as follows: lib. vi. 422.
Quod super est, facul est ex hiis cognoscere rebus,
Hence, with much ease, the meteor may we trace
* See Section vi.5.
To burst its bondage, oft the cloud itself
Oft, too, the whirlwind from the clouds around
The translator's note upon this passage, in exposition of bis author, is as follows, and we give it as affording a clear explanation of the nature and properties of this most singular and powerful meteor :
“Having discussed the phænomenon of thunder and lightning, he now proceeds to consider those of the water-spout, and the hurri. cane: and it is truly curious to observe how minutely he concurs with the philosophy of the present day, in regarding them as Meteors of a similar nature and origin. Prester, indeed, as our poet informs us, is a Greek word signifying a fiery or inflamma. tory intumescence; and such, he asserts, is the essence of which this meteor (the water-spout) consists: whence it is obvious, that the term ventus, or wind, applied to it immediately afterwards, is employed generically, to express an elastic gas or ether, for wbich Lucretius found no definite expression in his own language, rather than the nature of wind properly so called. It is an igneous or fiery aura, not indeed in the open act of combustion, but com. posed of the finest and most minute particles of a peculiar species of elementary fire, which, in a more concentrated form, would necessarily become luminous and burning.
“ Gassendi, indeed, contends, that the Epicurean prester is not an igneous meteor, but a mere vortex of elastic air. But there can be no doubt of his being mistaken ; for Lucretius not only employs a term to which fire, in some modification or other, either elementary or combined, is necessarily attached, but refers us, in the opening of the discussion, by way of explanation, to the constituent particles of lightning, which, he expressly declares, consist of the very finest and most attenuate fiery atoms.
“ Fiery, too, and of the common essence of lightning is this meteor asserted to be, by the philosophy of the present day. For it is regarded as an electrical phænomenon; as, indeed, is almost every atmospherical meteor, as well as a great variety that are subterraneous. In describing the powers and operation of the thunder-cloud, in note on v. 256 above, I have noticed its wonder. ful faculty of attracting, with almost instantaneous speed, the lighter and adscititious clouds in its vicinity, as I have also its submission to the still more strongly attractive power of that part of the earth which lies immediately beneath it, in a state of negative electricity, evidenced by its dipping downwards either in rage ged and multiform fragments, or, where the film of the cloud is tenser, in more regular and unbroken protuberances. Retaining then these simple facts in our recollection, it will not be difficult to account for the phænomenon of the prester, or water-spout, upon the principles of the electric theory.
" A thunder-cloud, or cloud filled with electric matter, is first noticed to appear at sea in a sky so serene as to be totally destitute of adscititious clouds, and in an atmosphere so dry, as to be pos. sest of very little and impalpable vapour. Such is the general ap- • pearance of the horizon on the commencement of the water-spout. In such a situation, a thunder-storm canoot be the result, for want of the confederate assistance of additional clouds and vapours: but, from the circumstances enumerated above, a very considerable portion of mutual attraction must take place between this isolated
cloud, and the portion of the sea immediately beneath it, more especially if the sea be at this time negatively electrified, or destitute of the electric power of which the cloud has a vast surplus. From this mutual attraction, the water directly under the cloud will become protuberant upwards, rising like a hill towards the cloud above, which, in the phænomenon we are now describing, it always does, and the cloud above will become protuberant downwards, elongating itself towards the elevated portion of water beneath. If, in this action of straining, the texture of the cloud be very slight, it will burst into a thousand fragments, and the electric matter contained within it will 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 appearance 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 deces. sarily 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 in. struments; 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 ordi. nary 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 so 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."