ITALY. L E T T E R . XI. 1 59 



end in fome flrata of the adjacent cinericeous hills ; 

 likely duft of pulverized black flaggifh lava. 



20. Grey or white puzzolana, or alhes dug in the 

 hills near Pozzuolo ; feems to be for the greater 

 part duft of grey cinders or pumice-ftones, pulve- 

 rized by long intenfe fire ; contains fome calcareous 

 or alcaline particles, more or lefs effervefcent with 

 the acids. The fame effervefcence appears in the 



21. Brown or yellowijh puzzolana, common in 

 the greateft part of the cipericeous hills at the foot 

 of Veluvius or about Naples. 



22. Smsll magnetic, black, fplendent cryftal- 

 line fherl-particles , by rain warned from the above 

 puzzolanic hills. They might perhaps be confi- 

 dered rather as fmall iron-cryftals, and certainly 

 have been expofed in the eruption to a ftrong uftu- 

 lation. 



23. Pumice-uones,- grey, black, or red, produc- 

 tions of the intenfeft fire, and the higheft degree of 

 fcorification- found in the cinericious hills, whence 

 they are vvalhed by the fea to the fhorc. The red 

 pumice-ftones in Pompejano are filled with white 

 fherl-garnets. 



24. Yellow native fulphur, plenty in the cracks 

 and fiflures of the inner funnel ; but the fnjalleft 

 part has got by fublimatioi: ,a determined form, the 

 greater part appearing in undetermined fmall 

 grains. 



2-. Red 



