265 
Dr Daubeny on the Geology of Sicily. 
some of the contiguous hills. The whole of this class, in short, 
though probably not formed under the pressure of the entire 
ocean, must have been produced, partially at least, under water, 
and that at a period antecedent to the existing order of things. 
This, indeed appears to be likewise the case with some of the 
lavas that occur in the neighbourhood of Etna, in the green- 
stone of the Cyclopean Islands, near Catania, which, though now 
severed apart from the mainland, and from each other, once 
constituted a continued stratum, that seems antecedent to the 
mountain, at the foot of which it is now placed. 
Amongst the other rocks on the same coast, that of Castello 
d’Aci would appear to be submarine, or, at least, of subaqueous 
origin. It consists of a volcanic breccia, the cementing sub- 
stance of a sandy nature ; the nodules a cellular kind of lava. 
The nodules, however, are not rounded masses, but result from 
a sort of irregular crystallization, most of them possessing a ra- 
diated structure, so that they resemble a clustre of prisms meet- 
ing in a common centre. The above stellular arrangement is 
the most common, but in other cases the prisms have more of a 
fan-shaped structure ; and, in both instances, the point towards 
which they converge, as well as the interstices between them, 
consist of tuff. 
It seems probable, indeed, from many circumstances, that the 
eruptions of Mount Etna commenced at an era not only an- 
tecedent to the time of Homer, but even perhaps to the com- 
mencement of the present order of things. If the existence of 
pebbles and other rolled masses, establish the operation of a de- 
luge, we have, in the gravel at the foot of Etna, abundant evi- 
dence of antediluvian eruptions, for both cellular and compact 
lavas are found among these deposits. Nor would it be difficult 
to point out, on the slope of Etna, especially on its north-east 
side, valleys which, from their size and figure, seem referrible 
rather to diluvial action, than to the effect of torrents. 
Perhaps the beds of lava at Aci Reale, to which Mr Bry- 
done refers in his entertaining Travels in Sicily *, where he 
* The following is the passage to which I refer, 
44 Near to a vault, which is now thirty feet below ground, and has probably been 
a burial place, there is a draw-well, where there are several strata of lavas, with 
earth to a considerable thickness over the surfuce of each stratum, Recupero has 
