18 
SALOON. 
Nat. Hist. 
also deposited some varieties of the cafs eye 
(mostly from Ceylon); a substance generally re¬ 
ferred to the natural order of quartz. 
Case 6. Besides some specimens of substances i 
related to common quartz, such as the avantiirino 
quartz, the Jieocible sandstone from Brasif and the 
iron JUnt(di substance in which oxide of iron ex- 1 
ists in chemical union with silica), this case con- ; 
tains varieties of the stalagmitical quartz^ also r 
called quartz sinter. The most remarkable among ‘ 
these are the siliceous concretions deposited by ' 
the celebrated hot spring in Iceland, the Geyser, 
one variety of which is called siliceous tuf^ the i, 
other calcedonic sinter. Another variety of it is ; 
the pearl sinter from Santa Fiora in Tuscany 
(whence it has obtained the name of Fiorite), ; 
and from the Island of Ischia. To this may also r 
be referred the ceraunian cinter^ or those enig- 1 
matical siliceous tubes which were first found in ; 
the sands of the Senner heath, in the county of ■ 
Lippe (where, from their supposed origin, they i 
are called lightning tubes), and subsequently,* 
under similar circumstances, at Drigg, on the i 
coast of Cumberland, which is the locality of the i 
specimen here deposited. [See also British Coll.] 
—The hyalite is placed here, as a mineral related 1 
both to stalagmitical quartz and calcedony.— ; 
The rest of this table-case and the greater partli 
of the following are occupied by calcedonic |i 
substances. Among the specimens of common 
calcedony, the most remarkable are, the smalt- 
blue 
to 
IS) 
