140 
EARTHS. ARGILLACEOUS. 4t. Scorliis. 
faces generally flreaked longitudinally, except where triiii' 
cated : fpccific gravity 3,2956. contains lilica 52.7. ale- 
mina 25,6. lime 9,4. exyde of iron 9,6. with a fmail 
of manganefe. Klaproth, 
iahularis. Hoary, femipellucid, confiding of very thin 4-fided table* 
compaited into thicker ones. 
Hoffmann Berg. Journ. 1788. x.p. 57, 
Found near Bourg ae Oifans in Dauphine, with the laft fpeciesi 
compafh, a little polilhcd, and foniewhat finning ir.tcrna'I)’i 
of a rather plane texture : the lateral faces of ihe tables cf' 
lindrico- concave, the terminal ones generally fligtitly coH' 
vex. 
• 
Diaphanous, fulvous, in 6-fided prifmatic cryllals. 
Hyacinthine. LaMethene Jo .rn phyf 1792. llo<v,p. 356. 
Vcfuvian. Thomfon chem. o,. p 599. 
Found fcatteredly in the lavas cf Kefu-vius, and was formerly 
confounded with the Hyacinth: colour fulvous-brown 
greeiiifh : is fometimes found cryftallizcd in redfangu’.ar *>' 
fided prifms, or rather 4-fided pnfins with their edges truD' 
cate : the primitive form of its c'ryftals is the cube : Tcratcbt® 
glafs: internal luftre 2, greafy j external 4, glafl'y : fraflit'' 
imperfcffly conchoidal : caufes double refraftion : melts 
fore the blowpipe into a yellowifli glafs; fpecific gravit/ 
. from 3,39. to 3,409. contains ftlica 26,5. magnefia 40;^' 
oxyde of iron 16,2. lime 16,0. Stucke. 
genuinut. Ponderous, opake, making a pale grey fcratch, 
Borax lapidofus. Sytl, nat. xii. 3. p. 95, n. 3, 
Corneus cryftallizatu*. Wall min. fp, 
Bafalt. fig. column. Wall.Jyst.x.p.-^xq.n.i, 
Shorl. Kir-vuan mineral, x.p, 265. 
Turmalin from Brafil. Schmeiffer mineral. l . p. 78. 
Black, Shorl. Thom/, chem, p. r 
Found in Cornnuall, where it is known under the name 
Cockle, in Ceylon, MaJagafear, Spain, Italy. Savilzerkti^l 
France, Hungary, Saxony, &c. in mafs, diflcmina'cd s'* 
cryttallifed, generally in Granite, Gneifs, and other fimfi/ 
rocks; the cryftals arc 3 or 9 fided prifms, which whenenth. 
are terminated by 3 fided pyramids; the furfice of the cO* 
tala longitudinally flreaked : the amorphous kind prefe'’ _ 
' th n llraight diftind columnar concretions, fometimes P® 
rallel, fometimes divergent or Ilellate, flreaked. and can ' 
V feparable from each other ; very fcldom in granular con'-W^ 
tions : the furface can be fcratchcd with a hard knife, 
when heated or rubbed hard is a little electric : vvhen hes>^^ 
to rednefs it becomes reddifh-brown ; is often fo nth ' 
iron, as to be atcrafled by the magnet : it afte4 upoi* 
