GALLERY.] NATURAL HISTORY. 163 
Case 11. Part of this Case is occupied by the speci¬ 
mens of sulphuret of arsenic, viz. the yellow orpiment, mas¬ 
sive and in striated, transparent, separable laminae; and 
the red orpiment or realgar, perfectly crystallized and 
massive.—The rest of this and part of the next Case con¬ 
tain the simple and double sulphur-salts formed by the 
sulphurets of antimony and of arsenic, with basic sul- 
phurets of electro-positive metals ; they are (besides some 
varieties of the plumose antimony or feather-ore)—the 
jamesonite or axotomous glance antimony the zinkenite, 
nearly related to plumose antimony ;—the red or ruby 
silver ore, divided into the dark and the light red, both of 
the same crystalline forms, but in the latter of which sul¬ 
phuret of arsenic takes the place of the sulphuret of anti¬ 
mony of the former;—the miargyrite of H. Rose, first 
separated by Mohs from red silver under the name of 
hemiprismatic ruby-blendethe sulphur-salt commonly 
called brittle vitreous silver (the roschgewachs of the Hun¬ 
garian miners) appears to be composed of the same con¬ 
stituent elements as the dark and the bright red ruby- 
silver ores, but in different proportions -, — bournonite, a 
sulphur-salt known also by the names of endellion, and 
triple sulphuret of lead, antimony, and copper ;—the 
scarce polybasite and in the next case. 
Case 12, the grey copper or fahl-ore (a double sulphur- 
salt, on the chemical constitution of which some light 
has lately been thrown by the researches of H. Rose), 
crystallized, massive, and disseminated in various sub¬ 
stances. 
The remaining substances in this Case are (besides the 
sulphuret of molybdenum or molybdena-glance) several of 
the arsenio-sulphurets, such as the arsenic-pyrites or 
mispickel (some varieties of which, containing accidentally 
admixed silver, constitute Werner’s weiss-ertz); cobalt- 
glance, massive and crystallized in the form of the cube 
and its modifications, &c. 
In the six following Cases the oxides of the electro-posi¬ 
tive metals are deposited. 
Case 13 contains the oxides and hydrous oxides of man¬ 
ganese, formerly distinguished as foliated, compact, and 
earthy grey manganese; but now generally divided into 
three species, called manganite, pyrolusite, and psilometane, 
