Note AX — Chapter XI

The valleys which separate these ridges form often spacious friths and bays, the frequent occurrence of which in the Old lied Sandstone constitutes, in some localities, one of the characteristics of the system. Mark in a map of the north of Scotland, how closely friths and estuaries lie crowded together between the counties of Sutherland and Inverness. In a line of coast little more than forty miles in extent, there occur four arms of the sea—the Friths of Cromarty, Beauly, and Dornoch, and the Bay of Munlochy. The Frith of Tay and the Basin of Montrose are also semi-marine valleys of the Old Red Sandstone. Two of the finest harbors in Britain, or the world, belong to it—Milford Haven, in South Wales, and the Bay of Cromarty.