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exclude this element from all share in the great proce's of exhalation, which, in all probability, it inspirits for the uses of vegetation and animal life, especially as Mr. Eeles has found by experiments, that all fumes arising from fire, whether blazing or otherwise, and all steams rising from boiling or warm waters, and from all other fluids, and the breath of man, and of all other animals, and all the effluvia thrown off by perspiration, are strongly electrified. He supposes that vapour and exhalation are detached from their masses by the vibrations of the electrical fluid rendered more active by the solar or culinary fire. He says, they are emitted in exceeding minute
distinct particles, and that these particles must pass through • that electrical Auid, which surrounds the surface of the mass;
and that, by that means, they must be equally electrified with the mass ; that is, they must be covered with the electrical fluid to as great a distance from their superficies as the mass is covered, which must always be in proportion to the
state of activity of the electrical Auid. In which state, when • they have passed the surrounding fluid, they must be repelled « by it; and also repel each other; and if each particle of va
pour, and its surrounding Auid, occupy a greater space than the same weight of air, they must be fitted to ascend till they come in æquilibrium with the upper and rarer part of the atmosphere; where they must float, until their specific gravity
is altered. As it is very difficult to assign the magnitude of * each particle of vapour and exhalation, and that of the sur(rounding Auid; and to shew, that both, taken together, oc*cupy a greater portion of space than the same weight of air ; we can only apply to experiment, to thew, that it is possible
that it may be so; and that will shew, that in all probability • it is so; since it is evident, that every particle must be en
dued with a portion of this electrical fire or Aluid, and that • there is not any other sufficient cause assigned for their 5 ascending.
• It is evident, that, upon electrifying any light matter, such as down, or the downy parts of feathers, their specific gravity is much lessened; and that, by holding another elec
trified body under them, they may be driven upwards at plea• furę. It is also evident, from experiment, that the more you Ç 3
divide <divide the parts of such bodies, the more of their specific gra
vity they will lose by being electrified; and by dividing them • into very minute parts, I have found, that they ascended to sa considerable height after they were electrified. From whence I think it highly probable, that the exceeding finall particles of vapour and exhalation may be, and are, sufficiently electrified to render them specifically lighter than the i lower air ; and that they do ascend by that means. And " that they will ascend proportionally higher, as the surround<ing fluid is proportionally greater than the particle, which is carried up.'.
Then he proceeds to shew, that the ascent and descent of this vapour and exhalation, are the principal cause of all our ( winds, and may account for the general phænomena of the " weather and barometer.' From this system, he pretends to thew, “firit, why it generally rains in winter, while the wind s is fouth, fouth-west, and wefterly. Secondly, why north' weft winds are generally attended by showers in the begin“ning, and become more dry, as they are of longer continu(ance. Thirdly, why north and north-east winds are gene« rally dry. Fourthly, why the cast wind continues dry and • dark for a considerable time together. Fifthly, why squalls
precede heavy and distinct showers; and why a calm ensues • for some little time after they are pass’d. Sixthly, why storms 6 and high winds seldom happen in a serene sky without clouds.
Seventhly, why the vapours, in warm seasons, coalefce to <form those distinct dense clouds, which produce thunder and « heavy showers. Eighthly, why the barometer falls lowest * in long continued rains, attended by winds; and why it rises highest in long continued fair weather; and why the intermediate changes happen. Ninthly, of land-breezes and fea• breezes, and water-fpouts.'
The theory is very ingenious, though liable to some objections, upon which the nature of our plan will not permit us to expatiate. We shall only observe, that he seems to be mistaken in his notion of water-spouts, which he supposes to be no other than heavy showers descending from dense clouds ; whereas, other philosophers have described them as great columns of water fucked up from the sea by the clouds. Unless he admits
the the possibility of such a suction, we should be glad to know how he will account for the descent of herrings, pilchards, and other smaller fishes, whole lasts of which have come down in one shower, in the northern seas and maritime places, according to the testimony of numbers of credible people, and among the rest, of that accurate historian and judicious philosopher, the right reverend Erich Pantoppidan bishop of Bergen in Norway.-_That the same suction is performed at land appears from great numbers of small frogs which have often descended in plump showers after violent explosions of thunder; a phænomenon which hath been fifty times observed in England by persons of undoubted veracity: nor is it so difficult of solution, as at first it may appear to be. Let us suppose a cloud charged with electrical fire, gravitating upon the furface of water, either in the ocean or within the land. This fire exploded above, so as not to destroy the texture of the cloud, may leave in the middle a momentary vacuum, into which the pressure of the atmosphere will forcibly impel a column of water with the fishes or frogs that swim in it, and these being scattered in the air by a subsequent explosion, must necessarily descend by their specific gravity.
The third letter of Mr. Eeles contains a recapitulation of the experiments by which he found all ascending vapours and exhalations were electrified.
• I extended a fine string of silk eight feet horizontally, and " from the middle suspended two pieces of such down as grows
upon our turf-bogs, by two pieces of fine filk, about twelve • inches each in length; and then, by rubbing a piece of feal'ing-wax on my waste-coat, over my side, I electrified the pieces of down: and then brought sundry burning things un. der them, so as to let the smoke pass in great plenty through and about them, to try whether the electric Auid would run
off with the smoke; but I had the pleasure to see that the s down was but a little affected by the paslage of the smoke, and still remained electrified. I then brought sundry steams from the spout of a boiling tea-kettle, and otherwise, in the
same manner, and still found, that the down remained electri"fied. I then breathed on them in great plenty, but found s that the down still remained electrified. I then joinded the
6 palmas of my hands together, with the fingers extended per< pendicularly under the down, which still remained electrified ;
although the subtile effluvia, thrown off by perspiration, passed
in great plenty through the down; as may appear by holding • one or both the hands in the same manner under any light « matter Aoating in the air, which will be driven upwards « thereby, with as great velocity as an electrified feather is by sany electrified body held under it. In short, I tried all the
vapours and exhalations I could think of, in the same manner, and with the same success.
I then warmed a wine glass, and with the skirt of my coat - held inside and outside the glass between my fingers and "thumb : I rubbed the glass briskly about, and electrified the 6 down, and found all experiments answer in the same manner 6 as they did with the wax. I mention this particular, because « some writers on electricity have said, that there were two • kinds of electrical fire, the one resinous, and the other vitresous; because light bodies electrified by glass are attracted by ç electrified wax, &c. and those electrified by refins are attractced by glass. But I think these different effects must arise * from some different qualities in the resin and glass, which have power to actuate this fire differently. For if there
were really two distinct species of this fire, opposite in « their nature ; the afore-mentioned experiments would have a « very different consequence from what appears. For if the « vapours were impregnated by the vitreous fire, they must ab• forb, or some way disturb, the resinous fire, which electrifies
the down, and so vice versa : but we find, that the same va6 pour, with its electric fire, passes through the electrified
down in the same manner, whether it be electrified by glass 6 or resin. But I will not detain you on this subject.
• The electricity remaining in the electrified down after these experiments made it appear, that the smoke and steams <must be either electrics, or non-electrics electrified. It was • easy to suppose them non-electrics, as they arise from non• electric bodies; and the more, because the highest electrics,
by a discontinuity and comminution of their parts (long be<fore they come to be as minute as the particles of ascending vapour), become non-electrics, or conductors of electricity. - For glass, resin, wax, &c, all become non-electrić, even in • fusion. But to try whether the steams, &c. were non-elec
trics, I only bedew'd the wax and glass with my breath, • steams, &c. from my hand to the end of the wax and glass;
and then touching the electrified down with the end of the • wax or glass, I found, that the electrical fire immediately passed from the down into my hand, through the steams, & c. which rested upon the wax and glass. Which, I think, sufficiently proves the steams, &c. to be non-electric; and I think, that it as plainly appears, that they are all electrified while ascending, because the electrical fire in the down does not join with them in their passage through it ; which otherwise it would do with them, or any non-electric not electrified.'
In the next article, the learned doctor Parsons presents us with a petrefaction which he dignifies with the name of Echinometra digitata secunda rotunda vel cidaris Mauri of Rumphius.
The proper classing of these productions, is a matter of greater consequence than the world generally imagines.—Were it not for the assistance of Rumphius, and other such philosophers, doctor Parsons might have stumbled over a stone, without knowing whether it was a pebble or a purbec, and be apt to confound a petrified crab with a common cockle-shell. We are afraid, however, that this great natural, with all his knowledge, has stumbled over an expression which hath dislocated the sense and meaning of the period. Flints and agates (Jays he) 6 are nothing less than crystal debased by earth.--'Now we should be glad to know whether he thinks there is any difference between nothing less, and nothing more?
What follows is a letter to the reverend Stephen Hales, D. D. F. R. S. from the abbé Mazeas, F. R. S. who mentions fome experiments, by which it appears, that the juice of the Toxicodendron Carolinianum foliis pinnatis, fioribus minimis herbaceis, strikes a fine black colour into cloth, and this colour adheres to it with more force than any other known preparation. He says, he tried the juices of two other species of the toxicodendron, growing in the garden of the Duke D’Ayen at St. Germain, and that they stained his ruffies of a finer black, and in much less time, than did the uice of the first mentioned. This effect the abbé seems to arrogate as a