\2i 
tals from Schneeberg in Saxony, derived from various 
modifications of calcareous spar; also beautiful speci¬ 
mens of wood converted into hornstone, being the 
wood-stone of Werner; hornstone balls from Haun* 
stadt in Bavaria .—Of flint, a well known substance, 
some interesting varieties are deposited. The remain¬ 
der of this and the whole of the following Case are oc¬ 
cupied by calcedonic substances. Among the speci¬ 
mens of common calcedony the most remarkable are, 
the smalt-blue variety from Felsobanyain Transylvania, 
crystallized in obtuse rhombohedrons; the branched and 
stalactical calcedony from Iceland, &c. ; the botryoidal, 
from Ferroe; nodules, including water (enhydrites) 
from Monte Berico, near Vicenza, where they occur in 
volcanic rocks. 
Case 23. Calcedonic substances continued: cut 
and polished pieces of calcedony with red and black 
dendritic and other figures, called mocha stones; va¬ 
rieties with white, brown, and black, straight or curved 
lines, some of which were probably among the sub¬ 
stances of which the costly vasa murrhina of the an¬ 
cients w r ere made; red and yellowish varieties of cal¬ 
cedony called cornelian. — Plasma. — Heliotrope 7 an in¬ 
timate mixture of calcedony and green earth, wdiich, 
when containing disseminated particles of red jasper, 
is commonly termed blood-stone.—The beautiful and 
much esteemed variety of calcedony called chrysoprase , 
hitherto only found at Kosemiitz in Silesia, and which 
owes its colour to oxide of nickel, as does the green 
siliceous earthy substance, named pimelite, which ac¬ 
companies it. To these are added specimens of some 
varieties of the siliceous compounds called agates , in 
which either common calcedony, carnelian, or helio¬ 
trope generally form a predominant ingredient. 
Case 24>. One half of this Case is occupied by the 
different varieties of jasper, such as they are enume¬ 
rated by Werner, viz. the globular or Egyptian jasper, 
found chiefly at Cairo in rounded pieces, which appear 
not to owe their form to rolling, but to be original, and 
produced 
LONG 
GALLERY. 
Nat. Hist. 
