gallery.] natural history. 117 
iii common with the silicate of zinc in Case 26) crystal¬ 
lized, botryoidal, and in other forms, among which are the 
pseudomorphous crystals, derived from modifications of 
carbonate of lime. 
Case 51. In this Case are deposited the specimens 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 variety, &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 mountain- 
blue ;—those crystallized varieties which, passing from the 
state of blue into that of green carbonate, have, by Hauy, 
been called cuivre carbonate epigene. 
Case 52. Carbonates of copper continued : green car¬ 
bonates ; among which are the fine and rare varieties of 
fibrous malachite, in acicular crystals, and massive with 
fibrous structure and velvety appearance, accompanied by 
carbonate of lead, &c.; and, among the specimens of compact 
malachite, those characteristic and splendid ones from the 
Gumashevsk and Turja mines, in the Uralian mountains. 
Case 53. Arsenious acid and arseniates: the former 
(also called arsenic-bloom, or octahedral oxide of arsenic) 
is frequently confounded with arseniate of lime, and the 
white octahedral crystals, often seen in collections, on 
realgar and orpiment, are generally artificially produced in 
the interior of mines.—Of arseniates we have in this glass- 
case :— arseniate of lime, called pharmacolite , chiefly in 
white acicular crystals, from Wittichen in Suabia, and 
Riegelsdorf in Hessia. — Arseniate of iron or pharmacosi - 
derite, which occurs only crystallized, chiefly in cubes 
(whence Werner’s name of cube-ore), from Cornwall, from 
San-Antonio-Pereira, Brazil, on hydrous oxide of iron, 
&c.;— skorodite, a substance which appears to be closely 
allied to Bournon’s martial arseniate of copper.— Arse¬ 
niates of copper, consisting of the foliated arseniate or 
copper mica, the lenticular arseniate or lentil ore, and the 
olive ore of Werner, which are formed into five species by 
