( ^24 ) 



ated nearly at the foot of the Euganean 

 hills, and proceeded with him, without de- 

 lay, to make refearches in them ; examin- 

 ing firft the ftones of Monte Caftello. 

 This is a fmall woody mountain, from 

 which arife feveral rocky points adhering 

 to the body of it, and affording three fpe- 

 cimens of lava. 



The firfl: has an argillaceous bafe, a 

 coarfe grain, and blackiih colour. It fhines 

 in many parts with black micaceous points, 

 and is fprinkled with reddifh fpots, like 

 thofe of feltfpar, in many oriental porphy- 

 ties ; and which are no other than Icaly 

 flakes of feltfpar, accompanied with a few 

 black fhoerls. 



that, when I wrote that Introduclion, I did not perceive 

 the importance of the fubjecl ; and of feparating the 

 ©bfervatlons I had made on other volcanoes from my 

 remarks on the Euganean hills. I likewife, at that 

 time, did not think it proper to mention this excurfion 

 particularly, as the remarks I made in the courfe of it 

 then remained unmethodized in my journals, and J 

 feared that I might not find fufiicient leifure to reduce 

 them to order, as I afterwards was enabled. 



The 



