MINERALS. 
5 
bitumen becomes Ojal. Scbift is however often refolvecl into earthy 
Ochre, which by multiplied mineralizatit n is regenerated into 'Toph. 
CALX, the earth of animals, combined with Natrum, alcaline, of 
a whitilh colour, abforbing acids, cafily fcraped with a knife, fa- 
rinaceous when dry, penetrable by fire, etfervefcing when burnt, 
calcifying moiil and argillaceous extraneous fiibftances into Marble; 
but when refulved and fatiirated with acid is recryltallized into 
Gypjurn, not again effi. rvefcing with acid without depuration by 
fire, and each is rcfolved by the elements into farinoiis Chalk, 
concreting by tethcreal water into Flint, but vvhen rcfolved is rc- 
cryltailized into Spar. 
Thele are the mothers of ftones. 
STONES grow from earths, are again rcfolved, and again repro- 
duced. 
Clay is attrafled into Talc, rcfolved into JFtthomarg, and rege- 
nerated into Amiant. 
Sand accretes together into Free-Jlone, is refolved into Gravel, 
and regenerated into Rock, 
Soil is cemented into Schid, rcfolved into Ochre, and regene- 
rated into Toph. 
Calx is coagulated into Marble, refolved into Chalk, and rege- 
nerated into Alabafter. 
Piaphanous fiones have their origin from a fluid rnother, opake 
(bnes from a fixed one. 'I'hcy are often tinged with a vitriolic 
alumen, varying in coloui according to their various tindtnres, and 
by thefe are Idled and confolidated with a cicatrix the fiifuies of 
rocks. 
Mica, the concretion of clay, is fcaly, flexile, opake, fhining, 
becoming more rigid in ignition and at the fame time more fhining. 
l^uartz, the cryftallization of elementary water, is pellucid, 
hard, from the watery cavities of rocks, and therefore always pa- 
rafitic, its cryftals being often obfcured by abrafion or by its bulk. 
Spar, the cryflallization of calcareous water, is diaphanous, 
fragile, w'hofe internal rhombs an adept willeafily dtllinguilh from 
a different cryflal ; adulterated with iron it becotaes harder and 
Ifrikes fire with fleel. 
CRYS'l'ALS are ftony, produced in and from water impregnated 
but not faturated with fait, which abounds with impalpable ter- 
reltrial atoms and is retained in the cavities of ftones They in- 
creafc by long and undiflurbed habitation, and are not again, folu- 
ble by water into impalpable atoms. In their many-fided figure 
they differ from all other Hones, nor have they any other however 
common to moll; falts, which is the foie caufe of cryftalization at 
prefent known, nor would falts have a determinate figure unlefs by 
