Fossils, though sparingly, are found in the graywacke, as trilobites and orthoceratites. The Braid and Blackford Hills are outliers of the Pentlands, and present the same varieties of rock and general lithological structure. Rapid and brief as the above sketch is, let the reader be assured there is much, very much, in the district to interest and instruct. Make the circuit of the Pentlands when he may, and he will not be satisfied until he has penetrated every valley, scaled every height, and become familiar as household words with every name and calling through the length and breadth of their varied range. Habbie’s How, a very pastoral in the sound, Carlops, Kaim-Valley, Mount-Maw, Deerhoperigg, Dalmahoy-Crags, the Mendick Hills, how dear to every lover of nature in their sweet retreats and cool shady banks! And Tintock, rich in prophetic lore, to be understood must be ascended, the eye ranging over the whole central valley of Scotland, embracing both oceans in its field of vision, and numbering all over the lofty granite peaks of the Grampians. Resting-spots like these impart a delicious charm to the geologist amidst his wanderings. If pregnant with the materials of doubtful reasonings, perplexing arrangements, and intricate soundings, the science has its sunny sides and cheerful fields of recreation. And if compelled to traverse regions of dangerous stepping, dark profound abysses, he is speedily again by the side of sparkling rivers, among grassy holms and pastoral dales, redolent with the bracing airs of crag and mountain. Nor are the moral influences of such speculations of a less healthful and refreshing kind. Geology, which deals with the cycles of time, is yet the youngest of the sciences. One exclusively of observation, all its objects lie scattered around the daily pathways of men. And still, but as yesterday, has it been looked upon with a favorable eye, as a means of investigating and establishing truth, and its truths themselves recognized as of good character and tendency. Herein, until very recently, the tree of knowledge was supposed to yield of its fruits of good and evil, most abundantly of the latter, and men long pertinaciously refused to partake of, or even to look at, the precious things that dropped from its numerous well-laden branches. Hume had attempted to demonstrate that there was no external world at all. Researches into the structure of mind, metaphysics, the domain of “common sense” as distinguished from the abstractions of the ideal philosophy, engaged and confounded alike the learned and the unlearned. Beneath, in the strata of the earth, lay the records and memorials, it was said, of vast untold ages, and all shrunk from an abyss on whose brink it was perilous to walk. The interior was literally regarded as unhallowed ground, from whose Pandora recesses, open who might, nothing but evils could issue, at utter variance with every fixed and established principle.