THE OLD RED SANDSTONE. 101 
has also its accompanying patch of Lias, which, though lying 
beyond the fall of the tide, strews the beach, after every storm 
from the east, with its shales and its fossils. The hill of Eathie 
is yet another knob of the series, and it, too, has its Lias 
patch. The granitic wedges have not only uptilted the sand- 
stone, but they have also upheaved the superincumbent Lias, 
which, but for their agency, would have remained buried 
under the waters of the Frith, and its ever accumulating 
banks of sand and gravel. I had remarked at an early period 
the correspondence of the granitic knobs with the Lias patches, 
and striven to realize the original place and position of the 
latter ere the disturbing agent had upcast them to the light. 
What, I have asked, was the extent of this comparatively 
modern formation in this part of the world, ere the line of 
wedges were forced through from below? <A wedge struck 
through the ice of a pond towards the centre breaks its con- 
tinuity, and we find the ice on both sides the wedge; where- 
as, when struck through at the pond edge, it merely raises the 
ice from the bank, and we find it, in consequence, on but one 
side the wedge. Whether, have I often inquired, were the 
granitic wedges of this line forced through the Lias at one of 
its edges, or ata comparatively central point? and about ten 
years ago I set myself to ascertain whether I could not solve 
the question. ‘The Southern Sutor is a wedge open to exam- 
ination on both its sides ;—-the Moray Frith washes it upon 
one side, the Cromarty Frith on the other. Was the Lias 
to be found on both its sides? If so, the wedge must have 
been forced through the formation, not merely Jeside it. It 
occurs, as I have said, on the Moray Frith side of the wedge ; 
and I resolved, on carefully exploring the Frith of Cromarty, 
to try whether it did not occur on that side too. 
With this object I set out on an exploratory excursion, ona 
