The disposition of land and water on this coast suggests the idea that the Western Highlands, from the line in the interior, whence the rivers descend to the Atlantic, with the islands beyond to the outer Hebrides, are all parts of one great mountainous plane, inclined slantways into the sea. First, the long withdrawing valleys of the main land, with their brown mossy streams, change their character as they dip beneath the sea-level, and become salt-water lochs. The lines of hills that rise over them jut out as promontories, till cut off by some transverse valley, lowered still more deeply into the brine, and that exists as a kyle, minch, or sound, swept twice every tide by powerful currents. The sea deepens as the plain slopes downward; mountain-chains stand up out of the water as larger islands, single mountains as smaller ones, lower eminences as mere groups of pointed rocks; till at length, as we pass outwards, all trace of the submerged land disappears, and the wide ocean stretches out and away its unfathomable depths. The model of some Alpine country raised in plaster on a flat board, and tilted slantways, at a low angle, into a basin of water, would exhibit, on a minute scale, an appearance exactly similar to that presented by the western coast of Scotland and the Hebrides. The water would rise along the hollows, longitudinal and transverse, forming sounds and lochs, and surround, island-like, the more deeply submerged eminences. But an examination of the geology of the coast, with its promontories and islands, communicates a different idea. These islands and promontories prove to be of very various ages and origin. The _outer_ Hebrides may have existed as the inner skeleton of some ancient country, contemporary with the main land, and that bore on its upper soils the productions of perished creations, at a time when by much the larger portion of the _inner_ Hebrides,--Skye, and Mull, and the Small Isles,--existed as part of the bottom of a wide sound, inhabited by the Cephalopoda and Enaliosaurians of the Lias and the Oolite. Judging from its components, the Long Island, like the Lammermoors and the Grampians, may have been smiling to the sun when the Alps and the Himalaya Mountains lay buried in the abyss; whereas the greater part of Skye and Mull must have been, like these vast mountain-chains of the Continent, an oozy sea-floor, over which the ligneous productions of the neighboring lands, washed down by the streams, grew heavy and sank, and on which the belemnite dropped its spindle and the ammonite its shell. The idea imparted of _old_ Scotland to the geologist here,--of Scotland, proudly, aristocratically, supereminently old,--for it can call Mont Blanc a mere upstart, and Dhawalageri, with its twenty-eight thousand feet of elevation, a heady fellow of yesterday,--is not that of a land settling down by the head, like a foundering vessel, but of a land whose hills