60 
NATURAL HISTORY. 
[north 
combined the davyne of Monticelli and several varieties of the elceolite or 
fettstein of Werner;— wernerite , under which name, formerly confined to 
some varieties of common and compact scapolite, are now by most miner- 
alogical writers united the meionite of Vesuvius, and the greater part 
of the scapolite , the parantliine , tlfe dipyre , the nuttallite , the bergman- 
nite; substances which, together with several others provisionally placed 
in this glass Case, stand in need of further investigation as to their chemi¬ 
cal and crystallographical characters. 
Case 32 contains micaceous and talcose substances. Our imperfect 
knowledge of the optical properties and chemical constitution of many 
varieties of the former, does not admit of their being arranged according 
to those distinctive characters ; such varieties as have been more closely 
examined in this respect, may be divided into potassa-mica (by far the 
most common), which has two axes; magnesia-mica , which has but one 
axis, in characteristic specimens from various localities, and particu¬ 
larly from Vesuvius, where it occurs in small, but briliiant and transpa¬ 
rent six-sided prismatic crystals; to this also appear to belong some 
varieties of mica called rubcllane , and the lithia-mica, which besides 
the beautiful peach-blossom, red, violet, greenish-grev, and white scaly 
varieties known by the name of lepidolite , (some varieties of which, how T - 
ever, are referable to the silicates combined with fluorides, in Case 58 A,) 
from Rozna in Moravia, likewise comprises several large-foliated va¬ 
rieties of what was formerly considered as common mica, such as that 
from Zinnwald in Bohemia and Altenberg, accompanied by apatite, tin¬ 
stone, and topaz. 
The species and varieties of the talcose substances are likewise 
very imperfectly understood. Among the specimens of talc in this 
Table Case may be specified the common or Venetian (which enters 
into the composition of cosmetics), and the indurated talc; to the former 
of which may probably be referred the green radiated talc from Siberia, 
composed of distinct groups of small diverging laminae, and which is 
known under the name of pyrophyllite ;— potstone, ollite , or lavezzo, (the 
lapis comensis of Pliny,) which appears to be an intimate mixture of 
talc and asbest, chiefly from Chiavenna, near Como, where it is 
manufactured into culinary vessels;— chlorite , crystallized in ag¬ 
gregated, small, modified rhombic prisms ; the earthy and foliated 
varieties, coating crystals of octahedral magnetic iron-stone, &c. ; 
chlorite slate;—the scarce leuchtenbergite from the Ural, the composi¬ 
tion of which appears to approach near to that of chlorite;— pinite, 
crystallized in regular hexagonal prisms, and gieseckite , from Green¬ 
land, which appears to be a variety of this species.— Fahlunite or 
triclasite, with the related weissite , from Fahlun in Sweden. 
Case 33. This and part of the following Case chiefly contain sub¬ 
stances related to hornblende or amphibolic minerals, among which may 
be specified the basaltic and common hornblende , including the parga- 
site ;—the actinolite or strahlstein (divided bv Werner into the glassy, 
common, and fibrous varieties, and to which also belongs the ka- 
rinthine of this author);—the grammatite or tremoiite (so called from 
Val Tremola, where, however, it is not found), among the specimens 
of which are the fine, fibrous varieties, resembling asbest; the glassy 
tremoiite, in dolomite and granular limestone, &c.— Arfvedsonite —ra- 
philite , &c. 
Case 34. Part of this Case is occupied by the mineral substances 
