102 THE OLD RED SANDSTONE. 
delightful morning of August, 1830. The tide was falling , 
it had already reached the line of half ebb; and from the 
Southern Sutor to the low, long promontory on which the 
town of Cromarty is built, there extended a broad belt of 
mingled sand-banks and pools, accumulations of boulders, and 
shingle, and large tracts darkened with alge. I passed direct 
by a grassy pathway to the Sutor, the granitic spear-head of 
a late illustration, —and turned, when I reached the curved 
and contorted gneiss, to trace through the broad belt left by 
the retiring waters, and in a line parallel to what I have 
described as the shaft of the huge spear, the beds and strata 
of the Old Red Sandstone in their ascending succession. I 
first crossed the conglomerate base of the system, here 
little more than a hundred feet in thickness. The cease- 
less dash of the waves, which smooth most other rocks, 
has a contrary effect on this bed, except in a few localities, 
where its arenaceous cement of base is much indurated. 
Under both the Northern and Southern Sutors the softer 
cement yields to the incessant action, while the harder peb- 
bles stand out in bold relief; so that, wherever it presents a 
mural front to the breakers, we are reminded, by its appear- 
ance, of the artificial rockwork of the architect. It roughens 
as the rocks around it polish. Quitting the conglomerate, I 
next passed over a thick bed of coarse red and yellow sand- 
stone, with here and there a few pebbles sticking from its 
surface, and here and there a stratum of finer-grained fissile 
sandstone inserted between the rougher strata: I then crossed 
over a strata of an impure grayish limestone, and a slaty 
clay, abounding, as I long afterwards ascertained, in ichthyo- 
lites and vegetable remains. There are minute veins in the 
limestone (apparently cracks filled up) of a jet black bitu- 
minous substance, resembling anthracite; the stratified clay 
