We returned out o f this hole, and eroding over the large cave
already defcribed, we came to the entry o f the third cavern,
which exceeds the other two in magnificence, largenefs, and
regularity of architedure. The caprice o f the (hepherds has
almoft lhut up the entry by throwing ftones into it. The *b*
mains, however, half open the fegment o f an arch well formed,
and which appears to have pilafters very regularly cut. Under
this arch, fometimes walking, and fometimes creeping, or letting
ourfelves Hide backwards, we got into the large cavern. It
is fixty-five to feventy feet in diameter, and about as. much in
height, and a hundred and fourteen in circumference. In the
middle of the roof, there is a circular aperture, like that o f the
Pantheon at Rome, which may be about twenty five feet in
diameter. * I f the arch o f this fubterraneous rotunda were not
embarraffed with ftones thrown in from above, it would form
a ftill more furpriling fpedacle. On the right and left hand o f
the entry, the ftrata are inclined in a ftrange manner, one againfl:
the other, and they appear to have been thrown into that not-
natural fituation by fome great ruin. The great convergent
angle formed by them ferves laterally for the vault. The fide
o f the cave bends a little above the arch o f the entry, though
not much,, on account o f its finall thicknefs, which increafes
in afcending from one foot to twelve, and forms .a divifory wall
about fixty feet high, between the hole in the middle and the
lateral one. Though the fubterraneous rotundo is not furniihed
with confiderable ftaladrtes, yet it deferves to be feen, defcribed
and drawn, for its largenefs, and ruftick regularity, which render
it fingul.tr. Nor ought this kind o f cryptography to be
reckoned ufelefs, or even of little moment. It has fuggefted
grand
* In the a a s of Coppenhagen of Bartclims, there is a defcription of a fimilar
cavern in Iceland. Ail. Barf. T. 3. Trukiltus Arngrimus defer.
grand ideas to the boldeft architeds; and befides tending greatly
towards the progrefs o f mineralogy, it often proves, inftruc-
tive in hydrography, and affords the molt ancient and incontrai-
tible documents o f the hiftory o f our globe.
From the many clefts, which run perpendicularly, and fometimes
obliquely into the mountain, and from the veftiges o f
■corrolion difcernible in the walls all around, it may eafily be deduced
that water has been the archited o f this work, operating
in feceret for many ages upon the hard marble. I dare not,
however, pofitively fay that the rain water began fo great an
undertaking, nor would I venture to afiert that the fubterraneous
running waters had effedcd i t ; becaufe many falient inequalities
in the rock, near the plain, and confequently fubjed
to an accurate examination, are pierced and corroded precifely
in the fame manner as the fea water ufes to corrode and pierce
the rocks of the fame fubftance. And here it is alfo proper to
remark, that the points of the rocks which remain bare on the
fuperficies o f the hill about thofe caverns are interfeded by holes,
windings, and cavities in the fame manner; and although thefe
are full of earth, and half covered with grafs, they appear plain
enough to an eye accuftomed to diftinguiih the work o f the
waves. Who knows what dreadful charybdis fwallowed up,
and regurgitated the fea waters from thofe concave rocks, in
what reuiote ages, more ancient than hiftory, or fable, or perhaps
than the boldeft conjecture o f man? And as a confirmation
that the waves of the fea, in former times, filled this fubterraneous
gulf, there appears introduced between the divifions
o f the convergent ftrata, a fecondary ftratum o f minute breccia,
o f very unequal thicknefs, which, by the nature o f its compo-
fition, manifeftly declares itfelf adventitious, and of pofterior
formation