14? 
triphane or spodumen and petalite , substances in 
which iithia, or the oxide of lithium, was first 
discovered by Arfvedson. 
Case 30. This case contains: nepheline , from 
Mount Vesuvius, with which are now com¬ 
bined several varieties of the elceolite or fett- 
stein of Werner; — wernerite , under which 
name, formerly confined to some varieties of 
common and compact scapolite, are now in¬ 
cluded the meionite of Vesuvius, and the greater 
part of the scapolite of Werner, the paranthine 
and also the dipyre ; substances which, together 
with several others provisionally placed in this 
glass case, stand in need of further investigation 
as to their chemical and crystallographical cha¬ 
racters. 
Case 31 contains micaceous and talcose sub¬ 
stances. In the present imperfect state of our 
knowledge of the optical character and chemi¬ 
cal constitution of several varieties of mica 
that have not yet been subjected to close ex¬ 
amination, no subdivision of the species as it 
now stands can be attempted beyond that into 
potassa-mica (by far the most common species), 
which has two axes; the magnesia-mica (from 
Vesuvius, Siberia, and Monroe, in New York) 
which has but one axis ;—and the lithia-mica , 
which, besides the beautiful peach blossom red, 
violet, greenish-grey, and white scaly varieties 
known by the name of lepidolite from Rozna 
l 2 in 
LONG 
GALLERY. 
