precipice about a hundred and fifty feet in depth, and see the waves dashing along the bottom. On descending by a somewhat precarious path, we find that a long, tunnel-like cavern communicates with the sea, and mark, through the deep gloom of the passage, the sunlight playing beyond; and now and then a white sail passing the opening, as if flitting across the field of a telescope. The _Gaylet Pot_ seems originally to have been merely a deep, straight cave, hollowed in the line of a fault by the waves; and it owes evidently its present appearance to the falling in of the roof for about a hundred yards, at its inner extremity. We pass from the conglomerate to the middle and upper beds of the lower formation, and find scenery of a different character in the districts in which they prevail. The aspect is less bold and rugged, and affects often long horizontal lines, that stretch away without rise or depression, amid the surrounding inequalities of the landscape for miles and leagues, and that decline to either side, like roofs of what the architect would term a low pitch. The ridge of the Leys in the eastern opening of the Caledonian Valley, so rectilinear in its outline, and so sloping in its sides, presents a good illustration of this peculiarity. The rectilinear ridge which runs from the Southern Sutor of Cromarty far into the interior of the country, and which has been compared in a former chapter to the shaft of a spear, furnishes another illustration equally apt.[AX] Where the sloping sides of these roof-like ridges decline, as in the latter instance, towards an exposed sea-coast, we find the slope terminating often in an abrupt line of rock dug out by the waves. It is thus a roof set on walls, and furnished with eaves. A ditch just finished by the laborer presents regularly sloping sides; but the little stream that comes running through gradually widens its bed by digging furrows into the slopes, the undermined masses fall in and are swept away, and, in the course of a few months, the sides are no longer sloping, but abrupt. And such, on a great scale, has been the process through which coast-lines that were originally paved slopes have become walls of precipices. The waves cut first through the outer strata; and every stratum thus divided comes to present two faces--a perpendicular face in the newly-formed line of precipice, and another horizontal face lying parallel to it, along the shore. One half the severed stratum seems as if rising out of the sea, the other half as if descending from the hill: the geologist who walks along the beach finds the various beds presented in duplicate--a hill-bed on the one side, and a sea-bed on the other. There occurs a very interesting instance of this arrangement in the bold line of coast on the northern shore of the Moray Frith, so often alluded to in a previous chapter, as extending between the Southern Sutor and the Hill of Eathie; and which forms the wall of a portion of the