and forming an interefting article of. commerce.*
* Meflrs. Brown and Co. the proprietors, are happy
to fiiew travellers their manufactory, and give them every
information. Their wholefale warehoufe in Taviftock-ftreet,
Govent-garden, exhibits the greateft variety of elegant urns,
vafes, &c. formed of this beautiful Hone, at the fame price
as at the manufactory; alio the moll Iplcndid and extenfive
collection of minerals in the kingdom.
SECTION
SECTION VIII.
Account o f other Minerals found in
Derbyfoire.
T h e gypfum or alabafter, naturally arifes
to obfervation, after the fluor, as being
employed in works of fimilar elegance.
This fubftance is found in large mafles,
filling up cavities or infulated places in the
argillaceous grit, near Derby ; as at Elvafton,
Chellafton, and Tetbury. It never forms
a ftratum, but is generally attended with
gravel, ftrong red clay, and an earthy covering,
in which are frequently innumerable
fhells.
The gypfum is generally veined with
red, and frequently with a dirty blue. No
mineral, or marine fubftances, are found
in it.
G 1 Gypfum