I 
2m A StstfeM 
of a pure^ and a very rich iron ore : Large veins of 
the fame ore are likewife found in almoft every 
province of that kingdom of fuch a nature, that 
few countries can produce better or richer. 
The magnetical power, with relpeft to its prin-* 
dples and origin, is no better underftood than 
eledlricity, yet fomewhat more with refpedt to its 
effedts. Though both thefe qualities are now con- 
fidered as different powers, they may perhaps in 
time be regarded as fomething nearer allied to 
each other. 
The magnetical power is not innate in the iron, 
but is colledted into it by degrees, which is veri- 
fied by experiments •, it may be expelled, it may 
'vanifh and gather again, as it were out of the air, 
iince the natural loadftones for the moft part occur 
in fmall veins to the day, whilfl: deeper, only refrac- 
tory iron ores are found. There is the fame differ- 
ence between an artificial magnet of Dr. Knight’s, 
and a bar of fteel, whether of the fame fhape or 
not, as between a natural loadftone, and a blackilh 
blue iron ore ; whence it is ridiculous to infift with 
a certain author, that no iron ore can be attradted 
by the loadftone, but what of itfelf contains fome 
magnetical virtue. 
SECT. eeXVI. 
The Second Order: 
S E M I-M E T A L S. 
There are but feven femi-metalsyet difeovered. 
viz. 
I. Quickfilver, Mercury, Argentum viv-um^ 
Mercurius^ Hydrargyrum, 
This diftinguifhes itfelf from all metals, by 
the following qualities. a. Its 
