54 Recovery of the Aachen Mass of Native Iron. (Jury, 
subject; but there they knew of no mass of iron whatever. It 
was then referred to Aachen, in another paper which appeared in 
1804, on native iron. Probably the mistake was discovered by the 
reference to the baths in the original paper. 
In the year 1812 Dr. Chladni wrote to the Consistorial President, 
Frederick Jakobi, at Aachen, requesting information respecting 
this mass of iron. As Dr. Lesoinne could give no intelligence 
respecting it, he and apothecary Monheim applied to the old town 
secretary, Couver. He recollected the digging up of the mass in 
1762, and that some pieces had been struck off, and deposited in 
the town-house, but had been soon after lost. The mass, he said, 
had been again deposited in the place from which it had been dug, 
and the surface again plastered over. Fourteen days after this in- 
formation Couver died, at the age of 78. 
Mr. Monheim gave this information to Trommsdorf, who pi 
lished it in his journal in 1812. Professor Weiss, in Berlin, endea- 
voured to interest the Academy in the re-discovery of this mass of 
iron in a town which belonged to the general government of 
Prussia. In consequence an order was obtained from the Chancellor 
Prince Hardenberg to the Governor-General Sack to fulfil the 
wishes of the Academy. 
The plaster being again removed, and the bottom examined for 
several days, the mass of iron was at last found, dug up amidst a 
crowd of people, and brought into the court of Mr. Biergans, Di- 
rector of the Circle, where it lies at present. 
It is covered with iron ochre, and, like all similar masses, is of 
an irregular shape, approaching to the oval. Its length is four feet 
nine inches; its breadth, two feet eleven inches; and its thickness 
two feet six inches; and its specific gravity, determined by a piece 
struck off from it, is 6°7. The whole weight amounts to about 
10,000 Ibs., supposing we reduce the size to 2 or 2 in order to con- 
vert it into a parallelogram. The coating ‘of ochre is half a line 
thick. _ Under it there lies a kind of bark half an inch thick, which 
may be easily separated from the stone. It is greenish, vesicular, 
and exhibits the marks of fire. Under this covering lies the native 
iron. It is extremely tough. In breaking off a few specimens, no 
fewer than eight chissels were broken. Mr. Monheim, a pupil of 
pair ns ng has not yet finished his analysis of it; but he has ascer- 
tained that it contains no nickel, but is composed of about + arsenic 
and 4 iron. Perhaps also there may be a third metal ; but it is in 
so small quantity that Mr. Monheim has not yet determined its 
nature.* 
How this mass has come to Aachen, we have no information. 
* According to the statement of Liber, the weight of this mass of iron was 
between 15, 000 and 17,000 Ibs., and it was covered with aceating from an half to 
one ineh in thickness. "It was malleable, and could be hardened and polished like 
the best English steel. Klaproth found no nickel in the 300 \bs. of native iron 
found at Villa, on the Collina di Brianza ; but in the 1301bs, from Elinbogen he 
found 2 2°5 per cent. of nickel.—Girperr, 
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