on the planes of which I
could trace with great distinctness ripple markings; but in vain did I
explore their numerous folds for the plates, scales, and fucoid
impressions which abound in the gray argillaceous beds of the shores of
the Moray and Cromarty Friths. It would, however, be rash to pronounce
them non-fossiliferous, after the hasty search of a single
morning,--unpardonably so in one who had spent very many mornings in
putting to the question the gray stratified beds of Ross and Cromarty,
ere he succeeded in extorting from them the secret of their organic
riches.
We set out about half-past ten for Scuir More, through the Red Sandstone
valley in which Loch Scresort terminates, with one of Mr. Swanson's
people, a young active lad of twenty, for our guide. In passing upwards
for nearly a mile along the stream that falls into the upper part of the
loch, and lays bare the strata, we saw no change in the character of
the sandstone. Red arenaceous beds of great thickness alternate with
grayish-colored bands, composed of a ripple-marked micaceous slate and a
stratified clay. For a depth of full three thousand feet, and I know not
how much more,--for I lacked time to trace it further,--the deposit
presents no other variety: the thick red bed of at least a hundred yards
succeeds the thin gray band of from three to six feet, and is succeeded
by a similar gray band in turn. The ripple-marks I found as sharply
relieved in some of the folds as if the wavy undulations to which they
owed their origin had passed over them within the hour. The
comparatively small size of their alternating ridges and furrows give
evidence that the waters beneath which they had formed had been of no
very profound depth. In the upper part of the valley, which is bare,
trackless, and solitary, with a high monotonous sandstone ridge bounding
it on the one side, and a line of gloomy trap-hills rising over it on
the other, the edges of the strata, where they protrude through the
mingled heath and moss, exhibit the mysterious scratchings and
polishings now so generally connected with the glacial theory of
Agassiz. The scratchings run in nearly the line of the valley, which
exhibits no trace of moraines; and they seem to have been produced
rather by the operation of those extensively developed causes, whatever
their nature, that have at once left their mark on the sides and summits
of some of our highest hills, and the rocks and boulders of some of our
|