C *7* 3 



VOLCANIC PRODUCTIONS, 



I. CINDERS. 



A. Loose. 



a. Ashes % of a brownifh or reddifli grey co- 

 lour; confiftence loofe and dufty; very light and 

 ftibtle, and fmooth to the touch; {lowly diffufible 

 in water, and when wet, fomewhat du&ile ; effer- 

 vefce flightly with acids ; and contain about half 

 their weight of argill, a fmall proportion of earth, 

 calx, magnefia, and iron, and the remainder is 

 liliceous. 



b. Sand; confiding of minute hard grains, that 

 readily fink in water /generally fragments of lava 

 and fcoriae, together with olivia, garnets, feltfpar, 

 and fchorl. 



B. Coherent. 



a. Puzzolana ; colour reddifli brown, grey, op 

 greyifh black ; that of Naples, grey ; that of Ci- 

 vita Vecchia, reddifh brown.-, furface rough, un- 

 even, and of a baked appearance ; pieces of va- 

 rious fizes, from the fize of a nqt to that of an 



