EARTHS. ARGILLACEOUS. 31. ArgUla. 119 



iiJuta. Somewhat meagre, a little plaftic when moiftened, dufty 



when dry, melting into folid glals in the fire. 

 Calx paluftns SyH. nat. xii. 3. p. 207. w. 5. 

 Argilla vix coherens. Wall. Jyji. i.p.6i tiiA. 

 Found in H'^iveden, chiefly und..r b> gs and marfhes, grey or 

 white ; the latter ii ufed for whitening walls. 



atvensis. Cinereous, forming fmall clods when moiftened, fplitM'ng 

 into large clefts while diying and becoming at lait 

 powd.ry, vitrifying in. the fire. 

 Ar^jlla humo mixta. Wall. Jyft. \ . p^ $^. n. w. 

 Found ev6ry where in cultivated lands. 



Umbra, Penetrated with bitumen, brown, making a mark, grow- 

 ing reddifh when burnt. 



Argiil-i humofa. Syd. nat. xii. 3. p. 204. r; 18. 



HumUi) colorata. Wall.Jyfl. min. 1,/). 17. n, 3, 



Umber. Kirivan miner ul, i. p 197, 



Martial clay. Schmefffer m'tieral. I. />. 164, 



Found in Britain^ Italy ^ iUrman\^ Sec, and is ufed ^y painters : 

 colour brown or blackifh, adheres to the tongue, and mode- 

 rately ftams the fingers : confifts prin:ipally of particles of 

 decayed wood mixed with bitumen. 



'vitriolacea. Brown,' ftiptic, turning a decodlion of galls black. 

 Argilla mixta fufca. Syji. nat. xii. 3. /, 205. ». 21. 

 Found every where under boggy land, and is a mixture of clay 

 and pyrites. 



salsa. Of a fait tafte. 



. Hiaerne tent amen chem. i. 

 Born. ind. fo/s. 2, /». 98. 



Found in the maritime parts of /luflriay and in the confines of 

 fait pits, cinereous or red, and is impregnated with muriate; 

 of loda. 



tohaltifera. Slack, forming a blue glafs when melted with borax. 

 Gefn, Hist. Cobalt. I. p. 21. 35. 

 Found in the mines of Wirtemburg. 



cupr-fera. Brown, producing a blue colour with heated fplrit of ani- 

 monia. 



Born, brief, J, p 33, 34. g. p, 43. 



Found in the mines of Germany; contains the oxydes of iron 



and copper, in the proportion of about 26 per cent, of the 



latter. 



srgenti/era. Soft, plaftic, exhibiting iilver when fufed with lead. 



Born. ind. fofs. 1. />. 83 84, 

 Ferber ul , die Gebirg, Ungar.p. 57. 



