LOADSTONE. 197 
Professor Pallas, many years ago, discovered lying on 
the surface of a hill in Siberia, a mass of native iron, 
which weighed 1680 pounds. It was considered by the 
natives as a holy relic, and was believed by them to 
have fallen from heaven. M. de Bougainville, the 
French circumnavigator, discovered, on the banks of the 
river La Plata, in South America, an enormous mass of 
native iron, which he calculated to have weighed about 
100,000 pounds. And a mass of native iron, appearing 
in every respect to have been of meteoric origin, was, 
some years ago, discovered in the district of St. Jago 
del Estro, in South America. It was in the middle of 
a great plain, and had no rock nor mountain near it, and 
was calculated to have weighed about thirty tons. 
The origin of meteoric stones is involved in great ob- 
scurity. Some writers have imagined that they might 
be projected from distant volcanoes ; others, that they 
may have been detached from rocks, and had their sub- 
stance considerably changed by a concurrence of na- 
tural causes ; others, that they may have been gene- 
rated in the air by a combination of mineral substances ; 
and others, that they may have been projected from the 
moon. The latter was the opinion of La Place the 
astronomer, who says that a mass, if thrown by a vol- 
cano from the moon, with a velocity of about a mile 
and half per second, it will thence be projected beyond 
the sphere of the moon's attraction, and into the 
confines of that of the earth ; the consequence of 
which will be, that the mass must presently fall to 
the earth, and become a part of it. 
235. LO AD STONE, or MAGNETIC IRONSTONE, 
is a compact blackish kind of iron ore, which is possessed of 
the power of attracting iron, as well as every substance which 
contains ferruginous particles. It is betwixt four and jive 
times as heavy as water. 
This mineral is found in masses of different form and 
size in most of the iron mines of Europe and America, 
and, when submitted to the furnace, it yields a consi- 
