220 Dr. ‘Cooper on Polcanoes 
“One of 1329 had 3 coating of 8 niches" 
One of 1669 — Bs S j eam 
One of 1766 ha a A ae 
In Italy, they are of opinion that the Cactus opuntia is 
better fitted than any other vegetable, to reduce the surface 
of Lava to. earth. 
Lavas are either submarine, or terraneous. Where they 
repose on, and alternate with strata, manifestly of marine 
origin, they may be considered as submarine. The volca- 
noes that elevate islands—those that alternate with madre- 
pore strata.as in the West-India islands. ‘The strata at the 
base of AStna consisting of Limestone with shells, Lava, 
then Limestone, and Lava are doubtless submarine ; “for the 
shell limestone on Lava must be a marine deposit. 
Other Lavas bear marks of being poured out originally 
on dry land, provided fleetz basalt should prove to be Lava ; 
as the hill Ng PS so Ger. de Soulavie says, he found 
wood cut with an axe, under a mass of Lava (Basalt) at 
Butaressa in Auvergne. ‘The same kind of occurrence is 
noted by M. Cocquebert at Meisner, where the Basalt 
three hundred feet thick covers a stratum of charred and 
bituminous wood in some places sixty or ninety feet high. 
Some of it cut in lengths with the marks of the Axe.and the 
Saw. Journ. des Mines No. 22. Breislak. § 701. 
Saulavie says, that in upper Vivarais none of the volea- 
noes-were submarine, but lower down. there are marks of 
the action of waves and the craters are obliterated. 2 Soul. 
353; A line of craters in that part of Erpnce, traced for 
sixty miles. 
The streams of Dave, fill up valleys and ae ae 
.. They are not conformable to the surface over which they 
flow, longer than. this fusion continues. They accumulate 
in thick and deep incumbent masses, frequently from sud- 
den congelation, exhibiting peaked eminences, like the ice 
congealed in our great rivers. 
‘They break through from below, and they cover from 
above, every stratum of ‘rocks without discrimination, that 
they happen to come into contact with. They produce the 
effects and marks of fire on the substances contiguous to 
them. 
The great mass of Lava streams consists of Basalt ; 
amorphous, tabular, columnar and figurate, compact, po- 
