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long enough for people to get out of their houses. Two people, that were out in it all the time, said, that they heard it coming about half a minute before they saw it; and that it made a noise resem. bling thunder, more continued, and continually increasing. A man came from St. Ives, who says, the spire of the steeple, one of the finest in England, was blown down, as was the spire of Hemming. ford, the towns having received as much damage as Bluntsham. There was neither thunder nor lightning with it, as there was at Cambridge, where it lasted above half an hour, and consequently was not so violent. Some few booths in Sturbridge-fair were blown down. The course of the storm was from Huntingdon to St. Ives, Erith, between Wisbeach and Downham to Lyno, and so on to Suetsham. Very few trees escaped : the barns that stood the storm, had all their roofs more damaged to the leeward side than to the wiodward. The storm was succeeded by a profound calm, which lasted about an hour; after which the wind continued pretty high till ten o'clock at night.
[Phil. Trans. 1741.
4. Tempest at Wigton in Cumberland.
By Mr. T. Thomlinson.
On the 6th of October, 1756, at night, happened a most violent hurricane, such as bas not been known in these parts in any one's memory. It lasted four hours at least, from about eleven till three. The damage it has done is very deplorable. The corn has suffered prodigiously. Stacks of hay and corn have been entirely swept away : houses unroofed, and in several places driven down by its fury: trees without number torn up by the roots; others snapt off by the middles, and their fragments scattered over the adjoining fields. Some were twisted almost round, or split down to the very ground; and, in short, left in such a shattered, mangled condition, as scarcely any description can give an adequate idea of. The change in the face of the country was very surprising in one single night: for, to complete the dismally-desolate scene, the several tribes of vegetables (in all their verdure the day before), as if blasted with æthereal fire, hung down their drooping heads. Every herb, every plant, every flower, had its leaves withered, shrivelled up, and turned black. The leaves on the trees, especially on the
weather side, fared in the same manner. The evergreens alone seem to have escaped. The grass also, in a few days time, reco. vered itself in a great measure.
Mr. T. agreed at first with the generality of people in their opi. nion, that lightning had done all this mischief: but on recollecting that there had not been much seen any where, in many places none at all, but that the effect was general, as far as ever the wind had reached; he began to think that some other cause might probably be assigned. Accordingly, he examined the dew or rain, which had fallen on the grass, windows, &c. in hopes of being enabled, by its taste, to form some better judgment of the sulphureous or nitrous particles, or of whatever other quality they were, with which the air was so strongly impregnated that night, as to produce such strange effects. Nor was he deceived in his expectations: for on tasting it, he found it as brackish as any sea, water. The several vegetables also which he tasted were all salt, more or less, and con. tinued so for five or six days after ; the saline particles not being then washed off, from the corn and windows in particular; the latter of which, when the moisture on the outside was exhaled next day, sparkled and appeared exceedingly brilliant in the sunshine. The saltness he conceived had done the principal damage; for common salt dissolved in water, he found on experiment on some fresh vegetables, when sprinkled two or three times, on them, has the very same effect, except that it does not turn them quite so black; but particles of a sulphureous or * other quality, may have been mixed with it. That this salt water had been brought from the seat, every body will allow; but the manner how I, is not 50 easy to conceive s.
[Phil. Trans. 1757.
* In an adjoining bleach-yard, a piece of cloth, which had been left out all night, was turned yellow; and was not without some difficulty wasbed out again. Some also, which was spread out the next day, contracted the same colour.-Orig.
+ The wind was westerly, and consequently would sweep the Irish sea.Orig.
No rain, or however very little, during the hurricane.-Orig.
Our readers will find various instances of such descent of saline particles in the preceding chapter xxxix, section v, where they will also perceive that the present writer must be mistaken in ascribing any part of the mischief to the salt.-EDITOR,
5. General Remarks on Tornados or Whirlwinds. It has long been supposed that these phænomena are immediately connected with atmospheric electricity, and produced by its irre. gular diffusion : and it must be obvious from the preceding articles in this section, that hurricanes, or wind-tempests, are precisely of the same nature as tornados or whirlwinds, only somewbat less de. fined and limited in their action.
The ancients supposed *, that there were great varieties of whirl. winds, of which Pliny and Seneca give different accounts.
The tyhon, Tuowy, is defined by them, vortex igne faetus, a vor. tex produced by fire, which causes dreadful hurricanes of wind, and destroys all things that come within its reach.
The prester comes from a grow, incendo, inflammo. It was said to break forth with strong flashes of lightning, and to be generally accompanied with an ecnephias.
The latter is from yemos, nubes, and is described as a sudden and impetuous wind, bursting forth from a dark cloud with little rain.
The exhydria was a violent whirlwind, attended with a great quantity of rain, and in fact the principal difference between an exhydria and an ecnephias was in the quantity of rain or water, which they were supposed to contain.
These whirlwinds are evidently of the same family, all the fea. tures of them being exactly similar, with some slight variations of character.
When a sudden and violent change is produced by fire, either common or electrical, in a considerable body of the atmosphere, the air from all sides suddenly rushes forward, and consequently concentrating to a point, forms a vortex; and when the cohesion of the air is broken, it will also of course precipitate the water it contains, and produce an ecnephias or exhydria; or where there is but little moisture in the atmosphere, a typhon or prester. The two first are probably the ascending whirlwinds, the others those which descend.
•Air ascending or descending, says Dr. Franklin, may form the same kind of eddies or whirlings, the parts of air requiring a circalar motion, and receding from the middle of the circle by a
• There is a little incorrectness in this explanation of whirlwinds, as the reader will perceive on turning to chapter zli, section is
centrifugal force, and leaving there a vacancy. If descending, it will be greatest above and will lessen downwards. If ascending, it will be greatest below and will lessen upwards, like a speaking trum. pet standing with the largest end on the ground.
When the air descends with violence in some places, it may rise with equal violence in others, and form both kinds of whirlwinds. The air in its whirling motion receding every way from the centre or axis of the trumpet, leaves there a vacuum, which cannot be filled through the sides, the whirling air as an arch preventing; it must then press in at the open ends. The greatest pressure in. wards must be at the lower end, the greatest weight of the sur. rounding atmosphere being there; the air entering rises within, and carries up dust, leaves, and heavier bodies, that happen to be in its way, as the eddy or whirl passes over land.
If it passes over water, the weight of the surrounding atmo. sphere forces up the water into the vacuity, part of which by de. grees joins with the whirling air, and adding weight, and receiving accelerated motion, recedes still further from the centre or axis of the trump as the pressure lessens, and at last, as the trump widens, is broken into small particles, and so united with air as to be sup. ported by it, and become black clouds at the top of the trump.
Thus these eddies may be whirlwinds at land and water-sponts at sea. A body of water so raised may be suddenly let fall, when the motion, &c. has not strength to support it, or the whirling arch is broken so as to admit the air falling into the sea. It is harmless, unless ships unfortunately happen to be directly under it; but if in the progressive motion of the whirl it has moved from the sea over the land, and there suddenly breaks, violent and mischievous tor. rents are the consequence.
6. Dreadful Whirlwind at Cambridge in New England.
By Professor Winthrop. The morning of July 10, 1761, at Cambridge, was fair and hot with a brisk gale at south-west. The afternoon was cloudy. About five it began to rain, and thundered once. At Leicester, forty miles westward, about five o'clock the sky looked strangely ; clouds from the south west and north-west seemed to rush to.
gether very swiftly, and immediately on their meeting commenced a circular motion; presently after which a terrible noise was heard. The whirlwind passed along from southwest to north-west. Its first effects were discernible on a bill, where several trees were thrown down at considerable distances from each other. In this manner it proceeded the distance of six miles with the most destruc. tive violence, tearing up and scattering about the trees, stones, fences, and every thing else in its way, forming a continued lane of ruins, of a few rods wide.
It met with only one dwelling-house in its course, that of one David Lynde, on which it fell with the utmost fury, and in a moment eflected its complete destruction.
The bouse was of wood, two stories high, and both the chim. neys of stone. Near the house were a shop and small shed ; and the barn stood on the opposite side of the road, about ten rods distant. As soon as they perceived the storm coming near the house some men within endeavoured to shut the south door ; but before they could effect it they were surprized by the falling of stones around them, from the top of the chimney which was in the mid. dle of the house. All the people in the house were in that in. stant thrown into such a consternation, that they can give no ac. count of what passed during this scene of confusion, which was indeed very short. Where the house stood nothing remained but the sills, and greater part of the lower floor, with part of the two stacks of chimneys, one about ten feet, and the other not quite so high ; the stones which had composed the upper part lying all around them. Except these sills, there were only three pieces of timber, and those very large, left entire; one of which, about sixteen feet long, and ten inches by eight, was found on the op. posite side of the road, nearly south, about twenty rods distant from the house. The rest of the timbers, from the greatest to the least, lay broken and twisted to pieces between N.N.E. and E. for seventy or eighty rods from the house ; some on the ground, others sticking into it a foot and two feet deep in all directions. Part of one of the main posts, about ten feet long, with part of one of the plats of nearly the same length, and a brace which holds them together, were left sticking in the ground, nearly perpendicular, to a great depth, in a field southerly from the house, about eight rods distant. The boards and shingles of the house, three or four