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the existence of atmospheric or meteoric mine-rals is fully admitted.

In the article native Iron , among the oresof that metal, the reader may find a few detailsrelative to this subject; and a reference toanother article Stones meteoric which bysome unaccountable oversight is wholly omitted.This omission it is the purpose of the presentarticle to supply.

Without adverting to the testimony of Livy,of Pliny , and of other ancient authors, I shallconfine myself to a brief enumeration of thoseaerolites which have either fallerf within thelast twenty or thirty years, or of which, thoughthe date of their fall is considerably moreancient, specimens are still extant, many ofwhich have of late been submitted to chemicalanalysis.

Those luminous bodies called meteors orfire-balls, which make their appearance at irre-gular intervals, traversing with an excessivelyrapid motion the upper regions of the atmos-phere, and ultimately falling on the surface ofthe earth, appear to be one source of meteoricstones. They evidently consist of a centralnucleus in such a state of softness or fluidity asto admit of considerable variations in its shape ;sometimes a disruption of the nucleus takesplace, accompanied by an explosion, and thetwo or three pieces into which the mass is thusdivided proceed in the direction of their pre-vious course without any apparent abatementof velocity. More usually however the ex-plosion is so violent as to break and dispersethe meteor, and the fragments immediatelyfall to the ground. Of these meteors some ofthe most remarkable and the best observed inmodern times are the following. On the 21stof May, 1676, a meteor was observed by Mon-tanan, professor of mathematics at Bologna ,and by others, passing with great velocityacross the north of Italy in a direction nearlyfrom E. to W. When it had arrived over thesea to the S.W. of Leghorn it burst with aviolent explosion, and its fragments, as they fellinto the sea, produced a hissing noise like thatoccasioned by plunging red hot iron into water.

On the 11 th November, 1761, a meteorwas observed in several of the provinces ofFrance . It burst with a loud explosion into agreat number of fragments in the neighbourhoodof Dijon , one of which fell upon a house andset fire to it.

On the 17th July, 1771, a meteor, traversingfrom N. toS. was observed in England and inFrance . It burst with a loud explosion S.W.

of Paris , causing a commotion like that of artearthquake. Its elevation above the surface ofthe earth, when first perceived, was more than80,000 yards, but at the period of its explosionit had descended to about half its formerelevation.

On the 18th August, 1783, a large meteor,traversing in the same direction as the preceding,was observed in various parts of England, ofFrance, and of Italy 2 s far as Rome . When itfirst was noticed, its apparent magnitude wa»about equal to that of the planet Jupiter , but itrapidly increased, and at the instant of its ex-plosion was of greater apparent magnitude thanthe full moon. Its form varied from round tooblong, and an internal movement like that ofebullition was distinctly visible: it divided intoseveral smaller masses, which continued in theironward course before the final explosion bywhich it was dissipated. The rate of its motion,according to the lowest estimate, was about Ifmile in a second.

The diameter of the nucleus of those meteo-ric bodies is variously estimated at from 100 to1000 yards; and it is obvious that a body ofmuch inferior size, moving with an equal ornearly equal velocity, would fail to attractnotice, especially in the day time, except at theperiod of its actual explosion. The greaternumber of instances of the fall of meteoricstones are under circumstances which renderit probable that they too are occasioned by theexploding of meteors, which their inferior mag-nitude alone prevents from being visible. Aloud noise, like that of thunder or the firing ofheavy artillery, or the overturning of a load ofstones, sometimes with, often without any visi-ble flash, is the first circumstance which attractsnotice and excites alarm, then a hissing likethe noise occasioned by the passage of a shotthrough the air is heard; a momentary glanceof the falling bodies is caught, and they areperceived entering the surface of the soil, thegrass and mould being at the same time thrownup on all sides, and a sulphurous odour dif-fusing itself to some distance around. Onimmediate search being made, by digging inthe direction of these holes, there is found,at the depth of a foot or two, a black roundishstone, sometimes large sometimes small, oftentoo hot to be held in the hand, and smellingstrongly of sulphur. Such are the generalphenomena; the most remarkable examples areas follow :

1. In the year 1492, according to SebastianBrandt, there fell from the sky at Ensisheim in