M IN E II A L O G Y. 
413 
Crcmentam - Solid, hardening in the air when pounded 
and kneaded with water and quicklime. 
Cariofus - - Rough, falling into powder in water. 
Ardefia - - Fiffile, when moiifened giving out an ar¬ 
gillaceous odour. 
Bafaltes - - Opake, without luftre, compaft, of a dull 
colour, eafily mouldering into pieces, 
melting into a blackiih glafs before the 
blowpipe. 
Lava . . - The produce of volcanoes or fubterrane- 
ous fires. 
Mica - - Scaly, fhining. 
Opa'us - - - Of no determinate fhape when broken, 
compact, melting with the greatelt diffi¬ 
culty. 
Zeolithus - Eafily melting with ebullition, and in melt¬ 
ing emitting a phofphorefcent light. 
Scorlus - - Melting, but emitting no phofphorefcent 
light. 
^rder V. Siliceous. Thefe are hard and very hard, and, 
except the fluoric, are not aftePted by acids ; fome are 
rupeitrial, others parafitic, and thefe lalt have often the 
vefiiges of living bodies. This Order contains feven- 
teen Genera: 
Gemma - - Cryftalline, hard and very hard, Aiming 
in the dark. 
Glucina - - White, infoluble in water. 
Olivinus - - Eafily falling to pieces in the air, melting 
with great difficulty. 
Feldfpathum Lamellar, melting with foda into a tranf- 
parent glafs : mouldering in the air. 
Pyromachus Not mouldering in the air, or melting 
without the greateft degree of heat ; 
breaking into convex fragments. 
Petrofilex - Melts without ebullition, of fliivery frac¬ 
ture. 
jafpis - - Opake, changing its colour in the fire, not 
melting by itlelf, breaking into convex 
fragments. 
Lazulus - - Hardifh, opake, of a fky-blue colour, not 
lofing its colour or effervefcing by acids 
fprinkled upon it. 
Smiris - - Of no determinate fliape, melting with 
great difficulty, very hard. 
Circonius - Ponderous, very fhining within, breaking 
into incurved plates. _ 
Amarus - - Tenacious, green, of fliivery texture. 
Lydius - - Fiffile, opake, of a dull colour, and of 
fliivery texture. 
Chlorogranatus Green, cryftalline, eafily melted by fire. 
Arena - - Confifting of dry hard rough granulations. 
Quartzum - Refilling the greateft degrees of heat, and 
all acids except the fluoric : fragments 
angular. 
Chalcedonius Refilling the greateft degrees of heat, and 
all acids : fragments more convex. 
Adamas - - Very hard, evaporating in fire with a flame. 
Order VI. Adamantine. Very hard, parafitical, con¬ 
taining an earth peculiar to itfelf,and hitherto detedled 
in no other foffil. This Order contains at prefent but 
one Genus: 
Adamantinus Refilling heat, fixed, hard, lamellar. 
Order VII. Aggregate. Thefe may be taken as a mix¬ 
ture of the preceding Orders, and confift chiefly of par¬ 
ticles, more or lefs cryftalline, adhering by a cement of¬ 
ten not vifible. The Genera are fix : 
Granites - Confifting of granular particles united to¬ 
gether without vifible cement and with¬ 
out regular order. 
Gneiflum - Of a lamellar texture. 
Porphyrius » Cryftalline particles imbedded in a llony 
palle. 
Nat rum 
Borax 
Muria 
Nitrum 
Amygdalytes Glandules more or lefs rounded, imbedded 
in a flony mafs. 
Breccia - - Fragments of Hone conglutinated by a 
llony or metallic cement. 
Arenarius - Granulations of filiceous Hones congluti¬ 
nated by a llony or metallic cement. 
CLASS II. SALTS. 
Thefe, by their talle and folubility in water, are known 
from all other mineral fubftances, and are dillinguifhed 
among themfelves by the kind of talle, and the degree of 
their folubility. Of this Clafs there are eight Genera : 
Of cauftic talle ; effervefcing with acids. 
Frothing in the fire, and in a ftrong heat 
melting into a tranfparent glafs. 
Of a fait talle, eafily foluble in water, 
changing nitrous acid into the nitro- 
muriatic acid. 
Of a cool lharpilh talle ; when moillened 
with very ftrongfulphuric acid emitting 
red vapours. 
Producing liver of fulphur in a white heat 
with powdered charcoal: its watery fo- 
lution not rendered turbid by a mixture 
of carbonat of foda. 
Of a bitter talle : its watery folution be¬ 
coming milky by a mixture of carbonat 
of foda. 
Of a fweetilh and very aftringent talle : its 
watery folution not made turbid by 
prufliat of foda. 
Of an acid aftringent talle : its watery fo¬ 
lution made turbid by a mixture of car¬ 
bonat of foda, or prufliat of foda. 
CLASS III. INFLAMMABLES 
Are charaflerifed by their folubility in oil, by their 
fmoke or flame when burnt, which is either grateful or 
difagreeable, innocent or deleterious, and by their colour 
or teint. This Clafs contains feven Genera : 
Turfa 
Bitumen 
Mellites - 
Succinum 
Mirabile - - 
Amarum 
Alumen - - 
Vitriolum 
Confifting of vegetable fibres interwoven 
together and penetrated with bitumen. 
Giving out a faint difagreeable fmell when 
burnt. 
Of a honey-yellow colour, in the form of 
fmall eight-fided cryllals. 
Melting with difficulty, and emitting an 
agreeable fmell during ignition, becom¬ 
ing eleflric by friction or heat. 
Ambra - - Softening and melting like wax in a gentle 
heat, and emitting a ftrong agreeable 
linell when warm; not becoming eleflric. 
Graphites - Burning with difficulty, but mixed with 
foda emitting reddilh flames and fparks; 
llaining the fingers black. 
‘Sulphur - - Burning with pale-blue flame, and emit¬ 
ting during combuftion ftrong fuft'o- 
cating peculiar fumes. 
CLASS IV. METALS. 
Metals are known by their lultre, great weight, proper 
flux, and folubility in acids. 
Malleable. 
Platinum - Silvery-white ; very hard and tenacious; 
fonorous ; exceedingly malleable and 
duftile ; not melting in awfliiteheat; 
foluble only in 16 times its weight of 
boiling nitro-muriatic acid, and giving 
firft a yellow and then a deeper red or 
brown colour to the folution. 
Aurum - - Reddiffi-yellow; hardifh and tenacious ; 
not fonorous ; exceedingly malleable 
and ductile; melting in a white heat; 
foluble 
