November 17, 1773, the Captain general of Sara gossa dispatched the following letter, accompanied with the stone to which it refers, to Don Manuel de Roda, Minister of State.
" In November last, an extraordinary occurrence, said to have happened on the 17th of that month, in a ploughed field at Sena, a village in the district of Si gena, was the topic of conversation in this city.
The sky being perfectly serene, three, reports, re sembling those of cannon, were heard, and followed by the fall of a stone, weighing nine pounds and one ounce, at a little distance from two labouring men. One of them went up to it ; but the strong smell whic,h it emitted stopped him for a moment.
a Recovering from his surprise, he went nearer, heaved it up with his spade, and waited till it was suf ficiently cold for him to carry it to the village, where he delivered it to the priest.
" From inquiries made immediately afterwards on the spot, and among the people in the neighbourhood, it appears that the noise in the air and fall of the stone were not accompanied with any storm or with light ning." This stone is still preserved in the Royal Collection at Madrid. Professor Proust, who was allowed to analyse it, on condition of leaving the principal portion untouched for the gratification of the curious, has fa voured the public with several particulars relative to its texture and aspect. When delivered to him, it weighed six pounds ten ounces. Along with it was a piece of three or four ounces, the only one remaining of those which had been broken from it by the inqui sitive. It was interspersed with spots of rust, both externally and internally, owing probably to its having been immersed in water, to try the effect of that fluid on its composition. Its shape was an irregular oval, seven or eight inches long, four or five broad, and four in its greatest thickness. One side was flittish, a lit tle depressed in the middle, and much rounded on the edges. It appeared to have had the black vitreous crust common to stones of this kind, though from its fra gility the greater part had fallen off in passing through many hands, and receiving occasional blows, so that none remained except in the hollow of the base, and a little on the faces of the pyramid. On examining this
crust, it was judged to be the effect of heat, powerful, though momentary, because the metallic and sulphu reous particles immediately beneath the crust had not had time to change colour, or even to lose their lustre. It had the porousness of an aggregate mass of arena ceous particles, without any cement, so that the breath would easily pass through a piece held between the teeth ; nor did it give sparks with steel. Its colour was a uniform bluish.grey, like that of a black sub stance, enlightened by a white one, or like the hue of an earthy compound, tinged by the least oxydation of iron. The rounded oval grains, of which the mass was composed, were very small, the largest being scarcely bigger than hempseed, among which were sprinkled metallic and sulphureous particles, charac terized by that light tint of kupfernickel, observable in most meteorites. The microscope ascertained that the earthy grains, so far from having been fashioned by the movement of water, were globules, rough with crystalline or reflecting points, so that they could not be confounded with common sand. A piece of about two inches being exposed to a red heat, in a crucible, for half a quarter of an hour, was much changed ; for the sandy globules became of a darker grey, and the metallic particles, deprived of their lustre, were sensibly oxidized. About two ounces were heated for half an hour, in a forge fire, which converted the stone into a semi-vitreous mass, blackish, slightly porous, and interspersed with globules of iron, which had not time to precipitate, though upwards of 100 grains of regulus were collected at the bottom. The magnetic iron was not uniformly mixed in the mass, as some parts yielded 22, and others only 17 per cent. This iron was combined with nickel, in the proportion of about 3 per cent.; but no nickel was traceable in any other part of the stone. After this alloy was separated by the magnet, the remainder was found, by analysis, to contain of Iron, sulphuretcd at a minimum, . 12 Black oxyd of iron,5 . .