Salts. 
Earths. 
14. Arenarius calcarius: grey, in fmaller grains, con- 
giutinated by a cement of chalk. Found in the moun¬ 
tain Kinnekulie in Sweden, forming the loweft ftratum ; 
when made red hot, it flies to pieces with a violent noife. 
15. Arenarius quadrum, or quarry-fandftone: liardilh ; 
conflfting of fmaller grains, conglutinated by a cement of 
marl. Found in Great Britain, Germany, Sweden, France, 
See. Grey, yellowilh, or reddilh, and forming horizontal 
or oblique clefts ; under ground it is moiit and eafliy cut, 
hardens when expofed to the air, but at length moulders ; 
is bibulous when quite dry, and leales off in a frofly air. 
It is principally ufed in architecture. 
16. Arenarius fulphureus : confilling of grains conglu¬ 
tinated by a cement of fwine-llone. Found in the lalt- 
pits of Gallacia. 
III. With an argillaceous cement. 17. Arenarius 
porcelanus : confilling of grains conglutinated by a ce¬ 
ment of porcelane-clay. Found in a coal-pit near Bofe- 
rup in Norway; under ground it is foft, but hardens 
when expofed to the air 5 and does not melt in the fire. 
18. Arenarius Fahlunenfis : confilling of minute white 
grains, with a cement of common rufous alumine. Found 
at Fahlun in Sweden, where it forms the bafe of copper- 
mines. 
19. Arenarius coloratus: confilling of fmaller and 
nearly-equal grains, varioufly tinged. Found fcatteredly 
here and there, of a yellow, green, blue, or reddilh, co¬ 
lour; and may probably be only a variety of A. ferrugi- 
nofus. 
20. Arenarius llratarius : hard, confilling of equal tranf- 
parent grains. Found almolt every-where : it hardens in 
the air, and is fait when found under fait w'ater. 
21. Arenarius friabilis .- confilling of minute grains 
flightly cohering. Found at Helfingburg in Norway. 
22. Arenarius fiflilis: feparable into tables or plates. 
Found in Great Britain, Sweden, Spain, Germany, &c. 
varying much in degrees of hardnel's, fize and tranfpa- 
rency of its grains, thicknefs of the plates into which it 
may be feparated, and colour; but is generally whitilh 
or reddilh. It may be ufed for tiling, unlefs it be too 
porous. 
23. Arenarius glareofus : foft, confilling of very mi¬ 
nute grains. Found commonly in Great Britain, Sweden, 
and Peru : colour grey, reddilh, yellowilh, or greenilh. 
IV. With a metallic oxyd fupplying the place of a ce¬ 
ment. 24. Arenarius amnigenius: hard, confilling of 
grains conglutinated by a cement of a fmall quantity of 
oxyd of iron. Found in Sweden and Germany ; of a red 
or yellow colour. The inhabitants near the river Hauki- 
pudas in Oltrobothnia, dig the fand from the bottom of 
the river, collect it into heaps, and leave it for a year or 
two to the influence of the atmolphere, when it becomes 
fo impregnated with iron that they form their hearths of it. 
25. Arenarius ferruginofus, or ferruginous landltone: 
confilling of grains conglutinated with a large portion of 
oxyd of iron. Found in Great Britain and Germany, of 
a brownilh or yellowilh colour, and is frequently imprefled 
with the calls of Ihells. It is fometimes fo rich in iron- 
ore as to be worked with advantage. 
26. Arenarius cobaltifer : confilling of grains conglu¬ 
tinated by oxyd of cobalt. Found in the mines of Ger¬ 
many. 
27. Arenarius cuprifer: confilling of grains conglu¬ 
tinated by a cement of oxyd of copper. Found in the 
mines of Siberia and Hefie. 
V. More compound. 28. Arenarius grifeus, or rubble- 
Itone : compofed of unequal grains cemented by indu¬ 
rated alumine, with frequently fragments of quartz and 
llate. Found in the Ural mountains of Siberia, in thole 
of Saxony and other parts of the continent, in flrata al¬ 
ternating with layers of (late and lydian-llone ; and is of¬ 
ten rich in metallic veins. The argil is bluilh-grey tend¬ 
ing to black; the grains generally white, rarely greenilh 
or red, but varying much in fize and proportion. Some- 
Vol. XV. No. 1058. 
473 
times it contains fpar, or bitumen, or the velliges of ani¬ 
mal or vegetable fubllances, with rarely a little mica. 
Specific gravity, 2’6 to 2 - 685. 
29. Arenarius novacularis : confilling of fmaller grains 
mixed with mica. Found every-w here in mountains and 
hills of fand, efpecially thole of a more recent date. Co¬ 
lour reddilh, yellowilh, rufous; the mica white or black, 
and difpofed longitudinally or in dots ; it hag generally 
a flaty, fometimes an undulately-flaty, texture ; and may 
eafily be feparated into plates. It is found in layers ; and, 
when broken, has a rather glittering clayey appearance, 
exhibiting mollly a fine grain. 
30. Arenarius molaris, mill-ltone, or Paris buhr: hard, 
confilling of unequal angular grains of quartz and fel- 
fpar interfperfed with mica. Is of a very hard texture, 
and is ufed for corn-mills. The grains of quartz are 
tranfparent, generally white, and larger; thofe of the fel- 
fpar are lefs, more opake, and grey. Found generally 
throughout Europe : it abounds in a great tradl of coun¬ 
try on the fouth-well of Paris, about Epernon, Dourdan, 
and Eltampes. See Mill-stone, p. 385 of this volume. 
31. Arenarius compadlus: hard, confining of grains of 
ochre-yellow quartz and red garnets. / 3 . Fiffile, and 
mixed with lilvery mica. Found in Dalecarlia and Weit- 
rogothia in Sweden ; and is ufed as a coarfer kind of mili- 
ftone. 
32. Arenarius radians: hard; variegated with columns 
of black Ihorl difpofed in a llellate manner, and inter¬ 
fperfed with grains of purple garnets. Found in Sweden; 
of a pale colour. 
33. Arenarius decuflatus: hard; reddilh-white, varied 
with black erefil and decuflating feales of hornblende. 
Found at Killamorac in Sweden. 
34. Arenarius frumentalis : varied with interfperfed fo¬ 
liations and lanceolate fpots of talc. Found in Germany. 
35. Arenarius variolofus, or tiger-ltone: white, in 
fmall grains; filtering water; with ferruginous perfo¬ 
rations. Found in Nericia and Wellrogothia in Sweden. 
The lpots and perforations originate from fmall pieces of 
pyrites imbedded, and which moulder into an ochraceous 
oxyd. 
CLASS II. SALTS. 
Aiurum, Bitter Salt.—Of a bitter tafte; eafily folu- 
ble in water, and the folution becoming milky by a mix¬ 
ture of loda; eafily melting in heat, but neither deto¬ 
nating or decrepitating. There are fix lpecies. 
1. Amarum genuinum, lulphat of magnefia, or Epfom 
fait: foaming in the fire, when dilfolved and evaporated 
cryflallizing into four-lided prifms terminating each fide 
in a four-fided pyramid, and which wither when expofed 
to the air. Found in many mineral waters of Great Bri¬ 
tain and other parts ; at Jena on gypfum, in Swifferland 
in a powdery llate, fometimes in "a llate of incrullatioa 
covering the furface of the earth ; in fea-water it abounds, 
and frequently renders the fait prepared from it bitter. 
Before the blowpipe it melts with difficulty into an opake 
glally globule. Its ufe is well known as a purgative; and 
the magnelia of the fliops is prepared from it, by dilfolviiig 
it in water, and precipitating the magnefia contained in 
it by means of alkalies. Specific gravity, 1 '66. Contains 
acid 33, magnefia 19, w'ater 48. Bergman. ■ 
2. Amarum munaticum : deliquelcing in the atnw- 
fphere, emitting acrid cinereous vapours of a difagree- 
able odour when lulphuric acid is poured on it, or it is 
expoled to a confiderable degree of heat. Found plenti ¬ 
fully in halt-waters, fprings, and lakes ; and converts 
nitric acid into nitro-munatic acid ; it is alio foluble in 
alcohol. 
3. Amarum calcarium : deliquefeing in the atinofphere, 
emitting acrid grey vapours of a difagreeable odour when 
fulpliuric acid is poured on it, but not when expoled to 
a violent heat. Found in the ocean and other Inline wa¬ 
ters, and fometimes in a dry Hate. Like the la.lt, it ccu- 
6 E verts 
MINERALOG Y. 
