mite and brown spar. Among the varieties of the first 
of these subspecies are those called miemite, tharandite , 
and some modifications of pearl spar ; among those of 
dolomite , a remarkable one is that from Pittsfield, Mas¬ 
sachusetts, North America, which exhibits a consider¬ 
able degree of flexibility : and another having the same 
property will be found among the singular varieties ot 
magnesian limestone from the vicinity of Sunderland. 
Among the varieties of Werner’s brown spar or pearl 
spar , which in some cases is with difficulty distin¬ 
guishable from rhomb spar, several interesting speci¬ 
mens for figure, colour and lustre, are deposited in this 
Case, and continued in 
Case 50, which is partly occupied by those fibrous 
varieties of brown spar, several of which were formerly 
referred to common fibrous limestone.— Carbonate of 
iron , or sparry iron ore , crystallized, fibrous, massive, 
and botryoidal {splicerosiderite of Hausmann).— Car¬ 
bonate of manganese, in globular and botryoidal shapes 
of various shades of rose colour, on sulphuret of manga¬ 
nese, &c. 
The remainder of this Glass Case is occupied by the 
several varieties of carbonate of zinc, (also called cala¬ 
mine, in common with the silicate of zinc in Case 26) 
crystallized, botryoidal, and in other forms, among which 
are the pseudomorphous crystals, derived from modifi¬ 
cations of carbonate of lime. 
Case 51. In this Case are deposited the speci¬ 
mens of carbonate of lead , or white lead ore, among 
which are the delicately acicular varieties from the 
Hartz, accompanied and partly coloured by green 
carbonate of copper; the crystallized varieties from 
Siberia, Mies in Bohemia; the pulverulent varie¬ 
ty, &c. It also contains part of the specimens of 
carbonate of copper , viz. the blue copper , or copper 
azure , the more remarkable varieties of which are 
those from Chessy, and from the Bannat, combined 
with various substances; the earthy varieties, some of 
which have been used as pigments under the name 
of 
LONG 
GALLERY 
Nat. Hist. 
