Actions of Volcanoes. 267 
ing where they were erupted, have been transported and conso- 
lidated by water. ‘ 
No blame, however, must be thrown on Signor Brocchi; his 
observations are, on the contrary, highly deserving of praise, 
as they are generally luminous, full, and well arranged, while 
they bear every mark of accuracy. It is no small.proof of 
this, that I have scarcely any where found a chasm or uncer- 
tainty among them, though deprived of the advantage of 
re-examining the facts on the spot; while the evidence appears 
nearly as perfect and as well connected, though made without 
the advantage of a correct hypothesis, as if, with that theory 
in my hand which I here presume to give, I had examined them 
for myself. Had this excellent geologist paid more respect to 
the theory of his countryman, Lazzaro Moro, the task of ex- 
plaining the facts which he has recorded would not have been 
left to another; but our science has long owed him a debt, 
which his successors, whether in Italy or elsewhere, seem to. 
have been most unaccountably unwilling to acknowledge. 
Those who may read these remarks, may probably feel some 
surprise that the late learned and keen illustrator of the Hut-. 
tonian theory, who enjoyed the advantage of a personal exami- 
nation of these appearances, did not come to the same conclusion. 
as I have done; particularly as that conclusion must have 
appeared to him so valuable for his peculiar views of a geological 
theory. I do not pretend to account for the omission; though 
we must remember that the same appearances do not always. 
make the same impression on every one. That omission must. 
not, however, be urged as an argument against the theory 
which I have here adopted ; since, without detracting from the 
high and acknowledged merits of Mr. Playfair, every geologist 
is aware, that his exposition of his favourite system is often 
deficient in known evidence, as it is often also negligent of 
insurmountable objections. 
In stating the facts from Signor Brocchi, I have been under 
the necessity of making a very severe abridgment; since, ina 
journal dedicated to original communications, it would have 
