bails,, in which thefe are wrapped up and confined. Iris
found, evidently ftratified, in uncouth beds of irrimenfe extent,
varioufly'inclined, which furniihes folid maffes of-al-
moft every fize and dimenfion,
si
T he largeft obelifks of Egypt have been hewn out of them.
When Chattered or broken by the irrefiftible ihock of earthquakes,
the impetuofity of torrents, when'womby the current
of rivers, or corroded or mouldered by the flower action
of ffpftjn.wind, and’weather, the horrid cruih a!nd downfall
of mountains prefents the granite blocks and ftrata in their
rude unwieldy iminenfity, wildly piled upon each other, fo
as to form, accidentally,' huts and cavfcms beheathi In the
fame manner, they appear naked and laid bare on the; weather
beaten tops and prominences of the higheft mountains.
T he .fiffures and divifions of the mafles appear in various
directions, agreeably to the force which has ailed upon them;
and in iome cafes they are wonderfully equipoifed and balanced
upon each other.
I h a v e been informed by an ingenious and learned friend
o f mine, well acquainted with the natural hiftory o f Cornwall,
that we need not go to Upper Egypt or the’Alps for the
ftudy of granite mountains; the whole fouth-wefterly end of
this ifland, beginning at Dartmoor in Devonfliire, and extending
through the whole country of Cornwall, to the re.
moteft cliffs and rocks of the Scilly Iflands, is more or lefs
a rtiafs o f granite, almoft every where interfered by metallic
veins i that this chiefly appears in Stv Michael’s Mount, in
Mount's Bay, on the fouthicdiftj tMt fome 'metallic veins' or
lodes, in the high toVverijigHi® on' the north Coaft, corroded
and decompofed by the furious battering- Of the lea, have left
ftupendous caverns and excavations, o f ; which he' inentions
one in Wicka Cove, between Stl Ives and' St. Juft, a§' particularly
• grand, and-' worthy ' the • inlpiebtidn Of the artift, as
well as of the natural hiftotian-.' :
lit calcareous, tnoftiy ftratified mountains, caverns are more
Various and -Common :• befides the accidental caveS- produced •
by the giving way and tiitnbling down o f mbutitAino-us maf>
feS, and the decbtnpofitionhf metallic and othef-lodes; more
extenfive and-fingular excavations are found in them, evidehti
ly produced by earthquakes,* or by the- decompofitionnf parts
o f the -rocky maffes, Or o f the ftratified rot-k fait, Which they
furrounded and covered, J* Such are, 1 anti informed, among
many others, the caverns near-Chadleigh and Plymouth, in
Devonfhire, and thofe which are fo juftly famous hear Caftle-
ton and Uuxton, in Derbyshire.. M thefelaft we behold the
undeniable prototype o f the lofty* femicirculaf1 dome, and o f
the arched vkult, o f which the hut Of the Grecians could not
fuggeft the idea. I deferibe them, from the accurate observations
o f the above-mentioned ingenious gentleman, ass wonderfully
regular, and as large conical excavations in the roof