ii6 EARTHS. ARGILLACEOUS. 31. Argilla. 



fissilis. Very foft, rather meagre and dry to the touch, adhering a 



little to the tongvie, of a flaty texiute, breaking into 

 difcoid fragments. 



Schiftus argillaceous. Syst. nat. xii, 3. p 5^. «. 7. 



Argilla vitref. £ffil. Wall.jyji. Tni». i. p 45, ;/. 4. 



Shiftofe cl.^y. Kirnvan mine' a/, i. p. 182. 



Slaty clay. Schmeifser miner, i. p, 168. 



Shiftofe clay. Thomfon chem, 3. p. 536. ' 



Found in Britain and various parts of Eiirope, in large layers, 

 generally over and under veins of coal, and is frequentlv pe- 

 netrated with bitumen: colour black or grey, rarely blue, 

 fometimes yellowilli, reddifli or brown, when it contains 

 much bitumen is of a blackifli-bro-.s n colour, appears iikc 

 bad coal, and burns with a weak flame and fulphure>us fmcll: 

 frcqueiitly bears the impreffion of plant?, clpecially thole of 

 the equifetum, adianthum and fern tribe; gives a vvhitiih or 

 grey itreak, and moulders gradually in water. 



sierilis. Somewhat meagre, lamellar, white when dry, growing 



reddifli and hardening a little in the fire, melting in a 



greater degree of heat. ' 



Argilla mixta. Syst. nat. xii. 3.^. 203. n. 14.^ 

 Argilla fiflilis alba. Wall. fyst. i. p. ^i:. n, ^* z. 

 Found in the barren ^\d\vi% oi Sudermannia in S^-eJen, efpecially 



where birch trees liourilh, and forms entire ftrata alternating 



with beds of fand. 



hullosa, Qreafy, foft, {hining by fri^^ion, adhering a Uttle to the 

 tongue, plaflic, growing reddifh and bliftery in the 

 fire 

 Found in Tranjylvania, 



Bolus, Greafy, fhlning by fri£lIon, dilTolving in the mouth, 



crumbling into powder immediately in water, grow- 

 ing reddifh and eafily diilolving in the fire, of a con- 

 choidal texture. 



Argilla ore liqu^fcens. Syst. nat. xii. 3. p. 203. n. 13. 



Argilla vitrefcens. WalUfyst.min. i. p 49. «. 8, 



Bolus. Cronft, min. 86. l^ogel mifi. p, "^^^ 



Bole. Kir<tvan mineral i. p. 190. 



Bole. Schmeifser mineral, l. p. 165. Thomfon chem, 3./ 587- 



2. Odorous earth from Portugal. 



Found in Armenia ^ Italy y France y and Germanyy and is frequent- 

 ly produced from decayed lavas: colour generally dull red or 

 brown, fometimes yellow, flelh-colour, cinereous, and in innu- 

 merable varieties; near Idria in Carniolay it is found mixed 

 with cinnabar, and nzvc Kafnick in Hungarxy combined with 

 (ilyer. 



