372 INDEX. 



Sherl-Fltrifications 



b. Tellow, like topaz in the fame Lavas, 150. 237*-.^, 



c. Black, called Pietre Oljidiane^ in the fame Lava 



150. 237. 



Silver -ere, in Lava, 65. 



Slags (Scoriae) artificial contain prifmatical cryftallizations, 258. 

 Slate (Schiftus). 



by the Italians called Lavagna, 299. 



(micaceous and argillaceous) ftratified, conftantly below 

 limeilone, fuperincumbent on Granite, 37. 125. 261. 



330- 



. Its fiflures and veins, filled with Quartz and other me- 

 tallic matrices, 37. 



Fiflures filled with Lava, 51. 



' 'i caufed by volcanic eruptions, ^3. 



Fragments in China-clay, 54. 56. 



Its near relation with Macigno, 261. 



Its relation with and difference from Granite. 



See Horn-Jlate. 



Slop (Dr.) at Pifa, 290. 



Soap-Jlone y called Pietra di Sarto, 292-* 



in Serpentine-Hone fiffures, 277. 



Sodflag, fpecies of Afbeft, 249. 



Solfatara, ancient volcano, 1 26. 1 64. 



^P' 

 Somma (monte). See Vefavius* 



Spadas cabinet in thepoffeffion of Mr. Seguier, 21. 

 Spalanzani (Laxaro), 



At Pavia, 3 1 8. 

 Sj>ar (calcareous). 



cotnpaft, and fcaly, from Vefuvius, 139. 



with Mica and Sherl-cryftallizations, 140. 



- (ciyjtattizcd), pyramidal, columnar, hexagonal, from 

 Vefuvius, 139. 



2 Spar 



