quantities of bog-iron embedded
in the soil, and presenting greatly the appearance of the scoria of a
smith's forge. The apparent scoria here is simply a reproduction of the
iron of the underlying flagstones, transferred, through the agency of
water, to that stratum of vegetable mould and boulder-clay which
represents the recent period.

I found the stack which I had been brought to see forming the
picturesque centre of a bold tract of rock scenery. It stands out from
the land as a tall insulated tower, about two hundred feet in height,
sorely worn at its base by the breakers that ceaselessly fret against
its sides, but considerably broader atop, where it bears a flat cover of
sward on the same level with the tops of the precipices which in the
lapse of ages have receded from around it. Like the sward-crested
hammock left by a party of laborers, to mark the depth to which they
have cut in removing a bank or digging a pond, it remains to indicate
how the attrition of the surf has told upon the iron-bound coast;
demonstrating that lines of precipices hard as iron, and of giddy
elevation, are in full retreat before the dogged perseverance of an
assailant that, though baffled in each single attack, ever returns to
the charge, and gains by an aggregation of infinitesimals,--the result
of the whole. From the edge of a steep promontory that commands an
inflection of the coast, and of the wall of rock which sweeps round it,
I watched for a few seconds the sea,--greatly heightened at the time by
the setting in of the flood-tide,--as it broke, surge after surge,
against the base of the tall dark precipices; and marked how it
accomplished its work of disintegration. The flagstone deposit here
abounds in vertical cracks and flaws; and in the line of each of the
many fissures which these form the waves have opened up a cave; so that
for hundreds of yards together the precipices seem as if founded on
arch-divided piers, and remind one of those ancient prints or drawings
of Old London Bridge in which a range of tall sombre buildings is
represented as rising high over a line of arches; or of rows of lofty
houses in those cities of southern Europe in which the dwellings
fronting the streets are perforated beneath by lines of squat piazzas,
and present above a dingy and windowless breadth of wall. In course of
time the piers attenuate and give way; the undermined precipices topple
down, parting from the solid mass behind in those vertic