MINERALOGY. 7 
i^emonftrate made upon the turf-moors which 
are at the foot of the hills or high rocks in the pro- 
vinces of Dalarne, Jemtland, and Flerjeadalen, 
in Sweden ? or, that certain vapours have pre- 
dominated, and ftill Ihew their power within cer- 
tain diftrife, where they attack, and fix them- 
felves to fuch matters as are moft agreeable to 
them ; fo that trees, which have been buried in 
the earth, in fome of its fubverfions, have met 
with martial vapours in fome parts of Bohemia ; 
the flint-producing principle of Loughneagh in 
Ireland, and at Adrianople ^ v/ith the. inflamma- 
ble fubftance in the ftrata of the coal-pits in Eng- 
land, and at Boferup in the province of Skone in 
Sweden ? or, that fhells muft, without the deftruc- 
tion of their calcareous principles, be changed in- 
to a calcareous fpar, as at the Balfberg in Skone ; 
be filled with flint, as at Vernon in France, and 
in Siberia ; or be penetrated with marcafite, as at 
Andrarum in Skone ; or with a green copper 
ore, as at Jarifberg in Norway ? Silver feems to 
predominate at Kongfberg in Norway, as the cop- 
per does in the north part of that kingdom : and 
the fame kind of ilone in which gold abounds 
at one place of the v/orld, ' may contain none at 
all at another place-, and other fuch examples oc-^ 
cur. 
I now leave this important fubjeft, that I may 
not difcover my farther want of knowledge there- 
in j but I take the liberty, at the fame time, to 
give this advice to beginners, viz. not to con- 
clude, that one mineral body is produced by ano- 
ther, only becaufe they are fituated near one ano- 
ther, if it cannot at the fame time be demonftrat^ 
ed by the analyfis, or by artificial mutation : nor 
to content himfelf with making his obfervatiQns 
only on cpliedions of minerals, or on heaps of 
B 4 ores^ 
