of thousands
on the exposed planes of its sea-washed strata, standing out in bold
relief, like sculpturings on ancient tombstones, at once mummies and
monuments,--the dead and the carved memorials of the dead. Every rock is
a tablet of hieroglyphics, with an ascertained alphabet; every rolled
pebble a casket with old pictorial records locked up within. Trap-dykes,
beyond comparison finer than those of the Water of Leith, which first
suggested to Hutton his theory, stand up like fences over the
sedimentary strata, or run out like moles far into the sea. The entire
island, too, so green, rich, and level, is itself a specimen
illustrative of the effect of geologic formation on scenery. We find its
nearest neighbor,--the steep, brown, barren island of Longa, which is
composed of the ancient Red Sandstone of the district,--differing as
thoroughly from it in aspect as a bit of granite differs from a bit of
clay-slate; and the whole prospect around, save the green Liasic strip
that lies along the bottom of the Bay of Broadford, exhibits, true to
its various components, Plutonic or sedimentary, a character of
picturesque roughness or bold sublimity. The only piece of smooth, level
England, contained in the entire landscape, is the fossil-mottled island
of Pabba. We were first struck, on landing this morning, by the great
number of Pinnae embedded in the strata,--shells varying from five to ten
inches in length,--one species of the common flat type, exemplified in
the existing _Pinna sulcata_, and another nearly quadrangular, in the
cross section, like the _Pinna lanceolata_ of the Scarborough limestone.
The quadrangular species is more deeply crisped outside than the
flat one. Both species bear the longitudinal groove in the centre,
and when broken across, are found to contain numerous smaller
shells,--Terebratulae of both the smooth and sulcated kinds, and a
species of minute smooth Pecten resembling the _Pecten demissus_, but
smaller. The Pinnae, ere they became embedded in the original sea-bottom,
long since hardened into rock around them, were, we find, dead shells,
into which, as into the dead open shells of our existing beaches,
smaller shells were washed by the waves. Our recent Pinnae are all
sedentary shells, some of them full two feet in length, fastened to
their places on their deep-sea floors by flowing silky byssi,--cables of
many strands,--of which beautiful pieces of dress, such as gloves and
hose, have been manu