t it could be derived from no great distance,--an outlier of the
Lower Lias. The icebergs of the cold glacial period, propelled along the
submerged land by some arctic current, or caught up by the gulf-stream,
gradually grated it down, as a mason's laborer grates down the surface
of the sandstone slab which he is engaged in polishing; and the
comminuted debris, borne eastwards by the current, was cast down here.
It has been stated that no Liasic remains have been found in the
boulder-clays of Scotland. They are certainly rare in the boulder-clays
of the northern shores of the Moray Frith; for there the nearest Lias,
bearing in a western direction from the clay, is that of Applecross, on
the other side of the island; and the materials of the boulder-deposits
of the north have invariably been derived in the line, westerly in its
general bearing, of the grooves and scratches of the iceberg era. But on
the southern shore of the frith, where that westerly line passed athwart
the Liasic beds of our eastern coast, organisms of the Lias are
comparatively common in the boulder-clays; and here, at Blackpots, we
find an extensive deposit of the same period formed of Liasic materials
almost exclusively. Fragments of still more modern rocks occur in the
boulder-clays of Caithness. My friend Mr. Robert Dick, of Thurso, to
whose persevering labors and interesting discoveries in the Old Red
Sandstone of his locality I have had frequent occasion to refer, has
detected in a blue boulder-clay, scooped into precipitous banks by the
river Thorsa, fragments both of chalk-flints and a characteristic
conglomerate of the Oolite. He has, besides, found it mottled from top
to bottom, a full hundred feet over the sea-level, and about two miles
inland, with comminuted fragments of existing shells. But of this more
anon.

CHAPTER III.

From Blackpots to Portsoy--Character of the Coast--Burn of
Boyne--Fever Phantoms--Graphic Granite--Maupertuis and the Runic
Inscription--Explanation of the _quo modo_ of Graphic
Granite--Portsoy Inn--Serpentine Beds--Portsoy Serpentine
unrivalled for small ornaments--Description of it--Significance of
the term _serpentine_--Elizabeth Bond and her "Letters"--From
Portsoy to Cullen--Attritive Power of the Ocean illustrated--The
Equinoctial--From Cullen to Fochabers--The Old Red again--The old
Pensioner--Fochabers--Mr. Joss, the learned Mail-guard--The Editor
a so