21 
eipal characters with the common ; specimens of 
those varieties which, having the property of be¬ 
coming transparent when immersed in water, are 
called hydrophanes, and vulgarly oculus mundi ; 
mod-opal , or opalised wood ; jasp-opal. , referred 
by some authors to jasper ; the menilite , called 
also liver-opal, found at Menil-Montant, near 
Paris, in a bed of adhesive slate, a specimen of 
which is added. Some varieties of cacholong 
may likewise be referred to the opal tribe.—The 
remainder of this case is occupied by the siliceous 
substance called hornstone , divided into the con- 
choidal and splintery varieties ; among these are 
the remarkable pseudomorphous crystals from 
Schneeberg in Saxony, derived from various 
modifications of calcareous spar, and generally 
referred to conchoidal hornstone; also some 
beautiful specimens of wood converted into horn¬ 
stone, being the mod-stone of Werner; horn¬ 
stone balls, from Haunstadt in Bavaria.— 'Flinty 
slate , &c. 
(Case 9.) In this case are deposited (besides 
the specimens of rock crystals continued from 
the opposite compartment of the table-case) the 
different varieties or subspecies of jasper, such as 
they are enumerated by Werner, viz. the globu¬ 
lar or Egyptian jasper , found chiefly near Cairo, 
in rounded pieces, which appear not to owe their 
form to rolling, but to be original and produced 
by infiltration; the ribbon jasper, or striped jas¬ 
per, the finest varieties of which are found in Si¬ 
beria ; 
SALOON. 
Nat. Hist. 
