I. I ſhall give the Reader a faithful Relation of this ſurprizing Phaenomenon it ſelf, from the original Ac⯑counts of ſome of the moſt intelligent of thoſe that ſaw it; which Accounts do here follow.

N.B. This utmoſt Altitude of about 20 Degrees at Yel⯑vertoft, agrees well with ſeveral Obſervations made at London, which ſeems to have been about the ſame Diſtance from the Meteor with Yelvertoft: For here it never appear'd conſiderably above 20 Degrees high.

N.B. The ſame Author afterward gave a more parti⯑cular Account of what he obſerv'd about this Meteor; of which the Epitome follows.

[9] N.B. That this Author's own natural Thoughts of the Meteor's Altitude, from his Obſervations, was between 38 and 40 Miles; tho' in this Letter he ſeems willing to extend it to about 50 Miles: And that another Audi⯑tor near Lempſter in Herefordſhire, eſtimated the Interval between the Light and the Sound by a Watch, and found it about 10 Minutes: Which gives about 40 Miles of Altitude alſo.

N.B. That Reſemblance of the latter Sounds to a Drum, I have heard confirm'd by more than one Au⯑ditor beſides.

[]

[15] N.B. That this curious Author's Computation of the middle Point of the larger Part of the Meteor, or of it when it was burſting to Pieces in its Exploſion, is ſcarce 22½ Miles. But then, that is only on the Suppoſition that that Point was perpendicularly over Plimouth, as ſome imperfect Accounts at firſt ſaid; whereas the Obſervati⯑ons by the Stars which are among the exacteſt I have heard of, compar'd with others already ſet down, will prove, That that Point was not then over Pli⯑mouth, but rather over the middle of Bretaign in France; which greater Diſtance will by the ſame Me⯑thod of Computation, afford us near forty Miles Alti⯑tude, which agrees with the moſt accurate Obſervations of the Interval, between the Sound and the Light, and with the reſt of the Obſervations by the Stars already ſet down; and indeed, with the Generality of the Obſer⯑vations every where that I have met with; and may therefore, I think, be entirely depended on by us.

NOW the proper Reſult of all theſe Accounts, and of many others that I have ſeen and heard, is this; That this Meteor was compos'd of Nitro-ſulphureous Vapours, or Exhalations, collected firſt together in the upper Regions of the Air, over Radnorſhire in Wales, or the neighbouring Counties: That it was at firſt ſmaller, and to Appearance like a large Star only; that it gathered more Fewel as it rolled along, and grew larger and larger all the Way; that its Courſe was nearly Parallel to the Horizon, and its Direction nearly South, or a very ſmall matter towards the South-Weſt: That by the time it came to be Vertical, between Cardiff in Wales and, and Minehead in Somerſet⯑ſhire, over the Severn Sea, it was become vaſtly large and bright, ſo as to exceed the Noon-day Sun in Splendor, near that Line along which it paſs'd, and [16] to equal its apparent Magnitude alſo: That it pro⯑ceeded in this manner quite over Devonſhire, but much nearer the Eaſtern Limits of it, than the Weſtern: That it paſt almoſt perpendicularly over the City of Exeter, and ſo over the Britiſh Channel, till it came over Bretaign in France: That all this while its Mag⯑nitude and Light were not impair'd; that it made a hiſſing Noiſe like a Rocket all the way, and ſpread a prodigious and continued Lightening, even to the utmoſt Limits of the whole Horizon: That upon its coming near to Bretaign in France, it began to burſt to Pieces and diſſolve, with a prodigious Noiſe, which endur'd for ſome time, anſwering to the time of its burſting to Pieces, all the while it was diſſolving: That it left a large Smoke, or ſort of Cloud along all that Space where it burſt, above 100 Miles in Length, over our Channel and Bretaign, and perhaps ſomewhat further towards Bell-Iſle: That the Noiſe of this Explo⯑ſionw as heard all along its Courſe, and 50 or 60 Miles at leaſt on both Sides of it; firſt like a vaſt Number of great Guns diſcharg'd together; and then like the rattling or interrupted Noiſe of Drums; ſuch as are in both Caſes uſual in and after great Claps of Thunder: That this Meteor, while it was diſſolving, ſeems to have ſent out leſſer Streams of Light, backwards to⯑wards Wales from the North-end; and backwards to⯑wards Exeter, from the South-end, before it intirely va⯑niſhed: After which, certain Traces or Streams of the fiery Vapors continued ſor a quarter of an Hour, as Marks where it had paſſed: That this Meteor muſt have been about 38 or 40 Miles in perpendicular Height from the Earth all along, tho' perhaps ſomewhat lower towards its diſſolution: That it went from Radnor in Wales, to the utmoſt Parts of Bretaign in France, or about 300 Miles, in 7 or 8″ of Time; or at the Rate of above 2000 Miles in a Minute: That it muſt have been viſible, wherever Clouds did not in⯑terpoſe, within the Compaſs of an Oval, whoſe lon⯑ger Axis, drawn nearly through Radnor and Bell-Iſle, muſt have been about 1400 Miles, and its leſſer at right Angles thereto about 1100 Miles, i. e. through [17] all Great Britain and Ireland; through Holland, Flanders, the Weſtern Parts of Germany, all France, and the North-Eaſt Parts of Spain, with Lombardy in Italy: And that it was really about a Mile in Diameter: That therefore it was truly a Meteor, or what properly, during its whole Courſe, was within the Limits of our Atmoſphere: As both the hiſſing Noiſe during its Paſſage, and the terrible Thunder afterwards, do plainly demonſtrate. It being well known that no Sound can be propagated, but through the elaſtical Medium of the Air. The remaining Traces of this Meteor left in the ſame Air, and ſeen therein for a quarter of an Hour after it was gone, are alſo evident Demonſtrations of the ſame thing.

II. I ſhall now give the Reader faithful Accounts of other Phaenomena of the like Nature with this Meteor before us, ſo far as they have hitherto come to my Hand.

(1.) The firſt Meteor of this kind that I have met with as ſeen in this laſt Age (for of the elder Ones we have generally ſuch imperfect Accounts, and that chiefly as Omens only, that little Light can be gather⯑ed from them, to any ſober Enquirer's Satisfaction) is that mentioned by Dr. Hook, in theſe Words.

[18] (2.) The ſecond Meteor of this kind, that I have met with was, in the Words of the ſame Dr. Hook ‘Ibid. p. 199.A Fax, or Lam⯑pas volans, obſerv'd after Sun-ſet, the 1 ſt of March 1676, at Fau—by Petrus de Lavina; at Rome, by Monſieur Auzout; at Florence, by Matthias del Arpi; at Venice, by Jo. Jacob Hertz; and in ſeveral other Cities of Italy: In all which it was ſeen alſo by very many others: And at the ſame time alſo, was obſerv'd in the lower Parts of Germany; as at Triers, by the Jeſuits there; Places very far diſtant from one another; and yet the Time and Manner of the Appearance in all was much the ſame. It ſeemed to riſe out of the North-Eaſt, and to paſs by the Me⯑ridian to the South-Weſt Parts of the Heavens, near the ſame Tract that the Sun had gone that Day; and diſappear'd behind thick Clouds, where, with a mighty Noiſe, it was ſuppos'd to be blown to pieces and diſpers'd. It appeared about the Bigneſs of the Full Moon, and left behind it a Tail about three Diameters, of a reddiſh Flame at firſt, but turning blewiſh towards the laſt. It laſted about a Mi⯑nute or two. Its Noiſe at laſt was like the Noiſe of an Earthquake at a Diſtance, and made the Glaſs in the Windows ſhake. From the comparing ſeveral Obſer⯑vations 'twas ſuppos'd about 90 Miles high, and near a Mile in Diameter.’

N.B. This muſt, in all Probability, be the very ſame Meteor which Montanari, the great Mathematician at Bononia ſaw, and exactly meaſur'd; of which pre⯑ſently. For it was ſeen in the ſame Year, in the ſame Month, at the ſame time of the Night, in the ſame Countries, and paſſed along the very ſame Courſe, and was of the ſame Bigneſs; as will appear immediate⯑ly. How the Day of the Month, March 1 for March 21, comes to be miſtaken, I do not certainly know; on⯑ly if they were both meant of the ſame Style, it is very eaſily accounted for.

[19] N.B. The real Altitude therefore of this Meteor was not 90 Mile, as 'tis here in general ſtated; but about 38 Miles rather, as Montanari particularly meaſur'd it; as we ſhall now ſee.

(2.) The Third, or rather the ſame Second Meteor of this kind I have met with, is that on March 21. 1676, about an Hour and three quar⯑ters after Sun-ſet, exactly, to a few Mi⯑nutes, within two Days of 43 Years before the laſt; which was an eminent one indeed, and was particularly ob⯑ſerv'd at Bononia, by that great Mathematician Monta⯑nari. "It came over the Adriatick, ſays Dr. Halley in his Extract from him, ‘Philoſophical Tranſact. No. 341."as from Dalmatia; croſt over Italy; and became nearly Vertical to Rimini and Le⯑ghorn: Its perpendicular Altitude was, at leaſt, 38 Miles; it made a hiſſing Noiſe as it paſſed, which was heard near its Courſe: From Leghorn it went off to Sea, towards Corſica: And at Leghorn it was heard to give a very great Blow, beyond the Noiſe of a great Cannon; with a Rattling, which conti⯑nued about a Minute or two. Its Velocity was not leſs than 160 Miles in a Minute: It was of an oval Shape: At 50 Miles Diſtance, its leſſer Diameter was as large to the Eye as the Moon's Diameter, and its larger above half as big again; ſo that its real leſſer Diameter was above half a Mile, and the o⯑ther more than three quarters of a Mile.’

(3.) The next Meteor of this kind, was that mentio⯑ned by Dr. Wallis, Sept. 20. 1676. about 7 at Night, which he deſcribes thus; ‘Philoſophical Tranſact. No. 135."There appeared a ſudden Light, equal to that of Noon-day, ſo that the ſmalleſt Pin or Straw might be ſeen lying on the Ground; and above in the Air was ſeen, (at no great Diſtance, as was ſuppos'd,) a long Appearance as of Fire; like a long Arm, with a great Knob at the End; for ſo it was de⯑ſcribed to the Dr. (who did not himſelf ſee it;) [20] ſhooting along very ſwiftly: And at its diſappear⯑ing ſeem'd to break into ſmall Sparks or Parcels of Fire, like as Rockets, and ſuch artificial Fire-works in the Air are wont to do. 'Twas ſo ſurprizing, and of ſo ſhort continuance, that it was ſcarce ſeen by any who did not then happen to be abroad; and laſted only while one might tell 15 or 20 at moſt. It was ſeen in moſt of the Southern Counties of England, at or near the ſame time. Nor could the Dr. ſatisfy himſelf which way this Meteor went.’

(4.) The next Meteor of this kind is that mentio⯑ned by Kirchius, as ſeen at Leipſick, May 22. 1680. ‘Philoſophical Tranſact. No. 341."about three in the Morning, as deſcending in the North, and leaving behind it a long white Streak. It was ſeen at ſeveral Places 160 Engliſh Miles diſtant from Leipſick, but met with no good Obſervers: as it is no wonder at that time of the Night.’

(5.) The next Meteor of this kind, was ſeen by Kirchius himſelf at Leipſick, July 9. 1686. ‘Ibid."at half an Hour paſt One in the Morning: which mov'd but ve⯑ry little for half a quarter of an Hour; its Diameter was about half as large as that of the Moon: Its Light at firſt was ſuch, you might read by it; but by degrees it vaniſhed away. It was ſeen in many Places at a conſiderable Diſtance from Leipſick; and and was at leaſt 30 Engliſh Miles high.’

(6.) The next Meteor of this kind, that I have met with, was ſeen by Monſ. Feuillee, a cu⯑rious Ir [...] Obſerver in the South-Sea, May 1 [...]. 1708. about Nine at Night. His Words are theſe: ‘Feuillee's Jour⯑nal. p 116.We ſaw, ſ ys be, a flying Fire, which being lighted all of a ſudden perfectly reſembled the Planet Venus; it remain;d in the Place where it firſt appear'd for a Minute and a half. I took care to obſerve it, by comparing it with the neareſt of the fixed Stars. On a ſudden it exten⯑ded it ſelf, and filled all the Horizon with Light, in ſuch a manner, that we might have diſcover'd a Ship [21] in any Part of the Horizon. This Light thus ſpread, laſted but a ſhort time.’

(7.) The next Meteor of this kind, that I have met with, was ſeen by the ſame Obſerver, a little above two Months after the for⯑mer, in the ſame Voyage, July 17. 1708. His Words are theſe; ‘Ibid. p. 199.In the Night, I ſaw a Phaeno⯑menon very Particular, almoſt like another that I had obſerved in the Northern Parts. As Aſtronomy has been always my chief delight, I was looking up to the Heavens to obſerve the Stars that make all its Beauty, and which compoſe the Southern Conſtella⯑tions. When I perceived on a ſudden a Star much greater than Jupiter and Venus, which continuing more than two Minutes in the ſame bigneſs, and without loſing any thing of its Light; I began to think, from its duration, that it was a New Star.—Whilſt I was employ'd in obſerving this New Phaenomenon, it hap⯑pen'd that this Luminary, as I could properly call it at that time, took Fire all on a ſudden; and,—ex⯑tending it ſelf throughout all our Hemiſphere, diſco⯑ver'd it to us intirely, and made us ſee to the furtheſt Limits of it, ſo that we might have ſeen a Ship at a great diſtance; and, if I may venture to ſay it, even in any Part of the Horizon; from whence, one may judge, how very great this Light muſt have been.’

(8.) The next Meteor of this kind, was ſeen in En⯑gland, July 31. 1708. between 9 and 10 a Clock at Night. ‘Philoſophical Tranſact. No. 341."It was between 40 and 50 Miles perpendicularly high; and that over Sheerneſs, or the Buoy on the Nore. It was ſeen at London, and in Suffolk, [and no doubt in the neighbouring Parts of England.]’ It appear'd at London to move horizontally, from E. by N. to E. by S. and in Suffolk it appear'd as ſliding obliquely downwards. It was very bright at its firſt Appearance, ſufficient to take up a Pin, and but a little inferior to the Light of the Moon; and it died away at the End of its Courſe, leaving a pale whiteneſs in the Place, without any Noiſe.

[22] This is an Epitome of the ſeveral Hiſtories of Me⯑teors of this Nature, that I have yet met with in the laſt Age.

(9.) Nor do I know of any the like Meteors ſeen ſince, till this before us; Unleſs we reckon that men⯑tion'd in our Gazette, and News-Papers, as ſeen over Venice, Feb. 22. laſt. But ſince it does not yet appear that this was ſeen at any conſiderable Diſtance, per⯑haps it might be ſomewhat of another Nature, and ſuch a Meteor as is ſeveral times ſeen in our lower Air.

III. I ſhall now give ſome Account of Dr. Wallis's Hypotheſis about ſuch Meteors; namely, that they are Comets: with my Reaſons againſt that Hypo⯑theſis.

Now as to this Hypotheſis, take it in the Doctor's own Account, Philoſ. Tranſact. No. 135. as ſet down by Mr. Lowthorp, in his Abridgment of thoſe Tranſactions, ‘"The Breadth of Ground, ſays he, where this Meteor, Sept. 20. 1676. was ſeen, was too much for any or⯑dinary Meteor in our lower Region of the Air to be ſeen in at once; which argues that either it was higher than it was imagin'd to be, (tho' the Light of it reached the Earth,) or elſe that it had a very ſwift Motion. This made me then conjecture, that it might be ſome ſmall Com t, whoſe linea trajectori [...] paſſed very near our Earth, or upon it; and might when farther diſtant from us, appear as a Comet And that Comet, which hath ſince appeared in Apri and May, confirms me in the ſame Opinion; which I conjecture may be the very ſame which paſſed by us in September laſt.’ So far Dr. Wallis. Now tho this Hypotheſis might be tolerable when it was writ⯑ten, before the true Theory and Motions of Comets were diſcover'd by Sir Iſaac Newton, and when the Dr ſeems not to have been acquainted with any other Ap⯑pearance of the like Nature, yet will it now no way bear. The Reaſon is obvious, viz. becauſe theſe Me⯑teors have no manner of Reſemblance to Comets at all [23] either in their Bigneſs, which is uſually about or under a Mile in Diameter; while Comets are uſually of the Bigneſs of Planets, or ſeveral thouſand Miles in Dia⯑meter: or in their Nature, which is that of Light or Fire; while Comets are ever as dark or opake in them⯑ſelves as the Planets; or in their Trajectory, which in Comets is a Line deſcending to, and aſcending from the Sun, and nearly parabolical; while theſe Meteors ſtill paſs in a manner parallel to the Earth's Horizon: or in their Velocity, which in theſe Meteors is very diffe⯑rent, but in Comets near the Earth is always the ſame; or in their Atmoſpheres, of which theſe Meteors are ſtill deſtitute; but which almoſt always encompaſs the Bo⯑dies of Comets, and that to a vaſt Diſtance; or in their Tails, of which we have no Signs in theſe Me⯑teors, but which almoſt as certainly accompany the Comets as do their Atmoſpheres themſelves, as in⯑deed derived from them: or in their viſible Duration, which in theſe Meteors is ſeldom many Minutes, fre⯑quently not many Seconds, but in Comets is uſually many Days or Weeks, nay ſometimes Months. To ſay nothing of the Impoſſibility there is that the ſame Co⯑met which was near the Earth in September ſhould con⯑tinue near it, or approach again to it ſeven or eight Months afterwards, as the Dr. ſuppoſes; when the Earth was then not very far from the oppoſite Point of its Orbit, or more than 100,000,000 Miles diſtant from its former Place. 'Tis therefore certain that theſe Meteors cannot belong to the Species of Bodies we call Comets.

IV. I ſhall now give a like Account of Dr. Halley's Hypotheſis about theſe Meteors; viz. That they are a ſort of fortuitous Collection of ſuch Vapours in the vaſt Void about us, as by Accident only fall into our At⯑moſphere, at certain times; without any other relati⯑on thereto; with my Reaſons againſt that Hypo⯑theſis.

Dr. Halley gives us his Hypotheſis, Tranſact. No. 341. p. 162. in theſe Words, ‘"I have, ſays he, much con⯑ſidered [24] this Appearance, and think it one of the hardeſt things to account for that I have yet met with in the Phaenomena of Meteors; and am in⯑duced to think that it muſt be ſome Collection of Matter form'd in the Aether, as it were by ſome fortui⯑tous Concourſe of Atoms; and that the Earth met with it as it paſt along in its Orb, then but newly form'd, and before it had conceiv'd any great Impetus of Deſcent toward the Sun. For the direction of that over Italy was exactly oppoſite to that of the Earth, that is, its Courſe was from W.S.W. to E.N.E. where⯑fore the Meteor ſeem'd to move the contrary way; and beſides, falling into the Power of the Earth's Gravity, and loſing its Motion from the Oppoſition to the Medium, it ſeems that it deſcended towards the Earth, and was extinguiſh'd in the Tyrrhene Sea, to the Weſt South Weſt of Leghorn. The great Blow being heard upon its firſt Immerſion into the Water, and the rattling like the driving a Cart over Stones, being what ſucceeded upon its quenching; ſome⯑thing like which is always obſerv'd upon quenching a very hot Iron in Water.’ Thus far Dr. Halley.

Now the plain Reaſons why I can no way agree to this Hypotheſis, are theſe:

(1.) 'Tis very evident, there neither is, nor can be any ſuch Collection of Vapours form'd in the Aether, as it were by ſome fortuitous Concourſe of Atoms, and without Gravity, which the Dr. here ſuppoſes as the Foundati⯑on of his Hypotheſis. Such a Maſs of Matter in an immenſe Vacuum, without any Gravitation to the Sun, the Dr. well knows is a mere Chimaera, contra⯑dicting all the certain Philoſophy in the World. Nor can it be poſſibly ſuppos'd but by immediate Creati⯑on out of nothing, or by it ſelf emerging out of no⯑thing, without being created, before it could be thus collected together; neither of which Notions, I imagine, will be juſtify'd by the Dr. himſelf, in his cool Thoughts. But let us for once ſuppoſe ſuch Maſſes of fiery Matter frequently collected in the Aether, tho' we know they cannot poſſibly be ſo collected; yet is it evident,

[25] (2.) That if ſuch Meteors as theſe were thence de⯑riv'd, they would appear at all ſorts of Diſtances, within the reach of their Light, or within the reach of a thouſand or two of Miles: For a Body ſo large, and a Light ſo nearly equal to that of the Sun, as theſe have, would certainly be viſible ſo far; where⯑as it does not appear, that any of them have been yet ſeen ſo far as 50 Miles from the Earth.

(3.) Theſe Meteors would, on ſuch an Hypotheſis, be equally of all Magnitudes whatſoever; ſuch fortu⯑itous Productions, if ſuch there were, going for cer⯑tain by no Rule at all: Whereas thoſe above-mention⯑ed ſeem never to have been of a larger Size than this laſt, which was about a Mile in Diameter; and the reſt of no very great Variety therefrom.

(4.) They would and muſt all, upon this Hypo⯑theſis, as the Dr. allows, in theſe Climates, go nearly with the ſame Velocity, and in the ſame Courſe, as to our Sight, i. e. from Eaſt to Weſt; becauſe their Motion being only apparent, muſt be deriv'd from the Earth's Motions, Annual and Diurnal, which are from Weſt to Eaſt, both the ſame way, and of one tenor. Whereas theſe Meteors go uncertainly, and without any regard to thoſe Motions at all. Accordingly, this laſt went almoſt directly South, and much faſter than even the annual Motion it ſelf; entirely contrary to this Hy⯑potheſis.

(5.) If theſe Balls of Light or Fire were ſuch Maſ⯑ſes as did not belong to our Atmoſphere, but only paſs'd through it accidentally, as Dr. Halley ſuppoſes; why do we not ſee them before our Atmoſphere reaches them? and after it leaves them, whenever it does ſo, as well as while they paſs through it? not to ſay, that the firſt Collection, as well as laſt Diſſoluti⯑on of theſe Meteors, does, by the Obſervations them⯑ſelves appear, both to begin and end within the Li⯑mits of that Atmoſphere, and thereby ſhew they pro⯑perly belong to it, entirely contrary to the Dr's. Hy⯑potheſis.

(6.) If this was the Origin of theſe Meteors, why do they ſeldom or never hit againſt the Body of the [26] Earth it ſelf, or terraqueous Globe, but againſt the Air? Or rather, why does the Body of the Earth or terraqueous Globe, ſeldom or never hit againſt theſe Me⯑teors, but only the Air, nay the upper Regions of the Air? Why do theſe Meteors ſeldom or never deſtroy a City, or burn up a Fleet, as well as paſs over our Heads, without doing us any Damage? The Earth's Diameter is near 8000 Miles; the Altitude of any ſen⯑ſible Atmoſphere, as Dr. Halley has fully prov'd, is not 50 Miles, and thence the Diameter of the whole, not 8100 Miles. Now the Disk or biggeſt Circle of the larger Sphere will be to the Disk or biggeſt Circle of the ſmaller here, as the Squares of thoſe Numbers, or nearly as 40 to 41, and the Difference of thoſe Squares, or the Hazard of ſuch a Ball's hitting againſt the Earth, or the Atmoſphere, will be as the ſmaller Number to the Difference of thoſe Numbers, or as 40 to 1. Nay, ſince only the upper Regions of the Air, for in them alone theſe Meteors have been ſeen, are to be compar'd with the Earth; it will appear on a like Calculation, that the Hazard of ſuch a Ball's hitting againſt the Earth, is to that of its hitting a⯑gainſt the upper Parts of the Atmoſphere, at leaſt as 100 to 1, or that, one with another, 100 of theſe ter⯑rible Meteors will hit againſt the Earth it ſelf, and de⯑ſtroy all before them, for one that hits againſt the upper Regions of the Air; and above 100 will hit a⯑gainſt either the Earth, or lower Regions of the Air, for one that hits againſt thoſe upper Regions; to which yet we ſee Providence uſually, if not always confines them. I ſay that theſe Meteors ſeem ſeldom or never to hit againſt the terraqueous Globe it ſelf.

'Tis true, Dr. Halley imagines, that thoſe which go off with a Report, as the principal certainly, and all probably do, muſt fall into the Sea, and in quenching make that Noiſe we hear after theſe Mete⯑ors, and that one of thoſe already mentioned deſcen⯑ded towards the Earth, and was extinguiſhed particu⯑larly in the Tyrrhene Sea. But then, ſince that is a bare Hypotheſis, and without any Fact or Hiſtory to ſup⯑port it, nay contrary to the known Obſervations them⯑ſelves, [27] while Dr. Hook's Account, ſet down as above, aſſures us, that the Italian Meteor which Dr. Halley ſup⯑pos'd to fall into the Sea, only ſet behind a Cloud, I ſhall not need to confute it any farther. In ſhort, this whole Hypotheſis ſeems to me ſo very weak, that it can only be excus'd and forgiven on account of the many other noble and truly excellent Performances of its Author. Tho' I confeſs I think this Author ſhould not eaſily forgive himſelf in one thing, I mean that odd Inſi⯑nuation here made, as if there might be a formation of Meteors, at leaſt, if not of other Bodies alſo, as it were by ſome fortuitous Concourſe of Atoms; which, I venture to ſay it, is, at this time of Day eſpecially, as little a⯑greeable to ſound Philoſophy, as to all the Notions we have of Providence and Religion.

V. I ſhall now propoſe a New Hypotheſis of my own, for the Solution of theſe Appearances, viz. That they are no other than prodigious Storms, or Blaſts of Thunder and Lightening in the upper Regions of our Air: With my Reaſons for that Hypotheſis.

Having therefore now given my Reaſons, why I cannot at all go into the Notions of either Dr. Wallis, or Dr. Halley in this Matter; I come to my own Hypo⯑theſis, or Conjecture; ſo I ſhall yet call it: Tho' I confeſs the Evidence for it ſeems to me ſo ſtrong, that, if the future Phaenomena of this kind do confirm it, as much as I think thoſe do which we are hitherto acquainted withal, it may perhaps hereafter merit a higher Denomination.

My Opinion therefore concerning ſuch Meteors, is plainly this, That they properly deſerve that Name of Meteors, as belonging directly to our Atmoſphere; and that they are no other than prodigious Storms or blaſts of Thunder and Lightening, of ſuch Thunder and Lightening, as is proper and peculiar to thoſe more elevated Regions of our Air in which they ap⯑pear. In order to the true underſtanding of my meaning in which Hypotheſis, the Reader muſt obſerve, that the Air at 39 Miles high, is, by Dr. Halley's Cal⯑culation, [28] agreed to now by all, about 2000 times ra⯑rer and weaker than it is here with us; that a Storm or Blaſt of this kind, even here below, ſeems to be a Collection of nitro-ſulphureous and fiery Vapors, into a ſort of a rolling Globe, or Whirl-wind of Fire; that this is that Fulmen or pernicious Lightning, which is ſo terrible in its Effects; that it is ſtill accompanied with that Fulgur or Flaſh, we call common Lightening, and with that Tonitru, that great rolling or rattling Noiſe which we call Thunder; and that ſuch Collecti⯑ons of nitro-ſulphureous or fiery Vapors may be vaſtly larger before they are limited or determined by the external Air, which by rarefaction is excluded from within, where it is ſo vaſtly rare, than the like Col⯑lections are with us: That the prodigious Velocity of ſuch Balls may alſo be better ſuppos'd in ſuch a rare and thin Medium, than in ours, ſo much denſer and thicker; and that ſo much the greater Quantity of nitro-ſulphureous Vapors will be ſpent and exhauſted by one ſuch Ball or Blaſt, than by one of ours here below, as it is in Magnitude greater; which will alſo render ſuch Phaenomena in the ſame Proportion rarer and ſeldomer in any certain region there than here.

Theſe things being ſuppoſed, which appear to me very reaſonable; it will be a natural Account of theſe Phaenomenona, if we eſteem them direct Blaſts of this kind. For certainly theſe Fire-balls, as we have ſhew'd, are ſtill within the Limits of our Air, the Place of ſuch Meteors: They have all the three Chara⯑cters of ſuch, and only of ſuch Blaſts; the Fulmen, the Ball or Whirlwind of pernicious Lightening; the Fulgur, the Flaſh or common Lightening; and the To⯑nitra, the Noiſe or Thunder. They go with a Swiftneſs which we have no Examples of here in any Meteors, unleſs it be in ſuch Thunder and Lightening. So that I do not ſee room for much doubt in the Caſe. 'Tis true, the rareneſs of the Air above, will, as in all like Caſes, greatly deaden and damp the ſound of the Thunder; as no doubt it does; but this is no great difficulty here, becauſe the prodigious Vaſtneſs of the Blaſt, if it be at all ſo much more violent as [29] the Fire-ball is greater in Quantity, as it muſt natu⯑rally be, will abundantly make up that Defect, and afford us a ſufficient Sound notwithſtanding; as will appear preſently by Calculation. I do not indeed know any mechanical Power, that in ſuch a fluid Me⯑dium as the Air, can cauſe ſo ſudden, and ſo prodigi⯑ous a Collection of fiery Vapors, and carry them in one particular horizontal Direction with ſuch an im⯑menſe Velocity as we here meet with. But then, I am equally at a loſs for the mechanical Cauſe of the ſtrange Effects of Gun-powder, and of the like Cauſe of the Velocity, Force, and Direction of Thunder and Lightening, and indeed of many other Powers of Nature; of whoſe Exiſtence, yet, there is no man⯑ner of Queſtion. So that if it appear, that this Me⯑teor is no other than a Blaſt of Thunder and Ligh⯑tening, ſuch as is proper and peculiar to the higher Regions of the Air, as I hope it now does; we ought not to object this Difficulty againſt the preſent Soluti⯑on, which is built on the known Properties of nitro⯑ſulphureous Vapors in all ſuch Exploſions, whether of Gun-powder below, or of Thunder and Lightening a little above.