"The largest specimen of these substances which has ever been described," observes Mr. Southey, " has escaped the notice of all the philosophers who have written upon the subject.
" Walkennaer, in a note to A zara's Travels, upon the mass of iron and nickel found in the Chaco, says that two other such masses have been discovered ; one which Pallas has described, and one which was dug up at Aken, near Magdeburg. Gaspar de Villagra, in his flistoria de la Xueva Mexico, mentions a fourth, evi dently of the same nature as these, and considerably larger than the largest of them. The tradition of the natives concerning it, supports the most probable theory of its origin. A demon, in the form of an old woman, appeared to two brothers, who were leading a horde or swarm of the ancient 'Mexicans, in search of a new country; she told them to separate, and threw down this block of iron, which she carried on her head, to be the boundary between them.
" Villagra describes it as something like the back of a tortoise in shape, and in weight about eight hundred quintals; he calls it massy iron ; it was smooth, without the slightest rust, and there was neither mine near it, nor vein of metal, nor any kind of stone any way re sembling it.
"The latitude where this is found is 27 N. The history of the expedition which Villagra accompanied, furnishes some clue for seeking the spot, and it might probably be discovered with little expense of time or labour. by a party travelling from Mexico to Mon terry." Humboldt's account of the Mexican sky-stone, re duces the above dimensions something more than a half; hut still it remains greatly larger than any other that has been yet discovered. " In the environs of Durango," 'says this philosophic traveller, " is to be found insulated in the plain, the enormous mass of mal leable iron and nickel, which is of the identical compo sition of the aerolithos which fell in 1751, at Hraschina, near Agram, in Hungary. Specimens were communi cated to me by the learned director of the Tribunal de Almeria de Mexico, Don Fausto d'Elhuyar, which I de posited in different cabinets in Europe, and of which M. M. Vauquelin and Klaproth published an analysis. This mass of Durango is affirmed to weigh upwards of myriagrammes, which is 400 more than the aero lithos discovered at Otumpa by M. Rubin de Cells. M. Frederick Sonnenschmidt, a distinguished mineralogist, who travelled over more of Mexico than myself, dis covered also, in 1792, in the interior of the town of Zacatecas, a mass of malleable iron of the weight of 97 myriagrammes, which, in its exterior and physical cha racter, was found by him entirely analogous to the mal leable iron described by the celebrated Pallas."
In the 42d and 44th vols. of Gilbert's Annals, men tion is made of meteoric iron at Elbogen, in Bohemia, which originally weighed 190 lbs. A fragment detach ed from it, and fashioned into the shape of a coin, has the peculiar property, when put into weak nitric acid, of being attacked unequally, and of then exhibiting blackish particles, and others, of a whitish hue, in re lief, whose mutual arrangements seem to depend on some law of crystallization. The Chevalier Schreibers, who first made this observation, found that it also ap plied to specimens of the Krasnojark mass; and he is inclined to believe, that it probably extends to all native iron that has fallen from the atmosphere.
Native iron is also supposed to have fallen near Lc narto in Hungary. Gilb. "Inn. p. 49.
Two masses in Greenland, from which the Esqui maux manufacture a sort of small knives. Ross's Ac count of an Expedition to the Arctic Regions. Edin. Journ. of Science, No. 1.
A few other detached masses of native iron have been quoted by different writers ; but as they contain no nickel, and have a different texture from the pre ceding, their meteoric origin seems to be extremely doubtful.
From the foregoing historical review of our subject, we may safely deduce a few general observations, or corollaries.
That meteorites do really fall from the upper regions of the air to the earth, can no longer be doubted, un less we are determined to reject the evidence of hu man testimony. These bodies have a peculiar aspect, and peculiar characters, which belong to no native rocks or stones with which we are acquainted. Their fall is usually accompanied by a luminous meteor, which is seldom visible for more than a few minutes, and generally disappears with explosions. These bo dies appear to have fallen from various points of the heavens, at all periods, in all seasons of the year, at all hours, both of the day and the night, also in all coun tries of the world, on mountains, and in plains, and without any particular relation to volcanos. The lu minous meteor which precedes their fall, affl ets no constant or invariable oirection. They are, for the most part, hot when they fall, and emit sulphureous vapours. As their descent usually takes place in calm, and often cloudless weather, their origin seems to be owing to some very different cause from that which produces rain or storms.