II. In the general structure of the environs of the Scottish metropolis this plutonic machinery is deeply impressed, as it has been most vigorously exerted. There is everywhere the greatest derangement existing among the sedimentary deposits, everything is tossed out of its original place, and divided into small sections and detached groups. The connections and relative positions are very difficult to trace. Still, amidst all the disorder, the more general bearings of the different formations may be ascertained. Mr. Charles Maclaren, indeed, has examined everything with a pains-taking care, and described them with a minuteness and fidelity of detail, which cannot be surpassed, as they need scarcely be repeated. His “Geology of Fife and the Lothians,” will be in every student’s hands who desires to be acquainted with the structure of the district, conversant more especially as this learned geologist is with the position, fragments, and medal-stamp of every rock—their relations to each other, historical value, and bearings in the science—and illustrated with such diversity of section and diagram, that we feel as we accompany him,— “Panditur interea domus Omnipotentis.” The general contour of the city, so picturesque and remarkable in its grouping of streets, may be taken as a pretty safe guide in determining the nature of the geology. The town is built over two parallel ridges, which completely expose the character of the inferior minerals. The northern division rests upon a series of beds, which appear immediately to underlie the true workable coal seams; the Old Town ridge and Castle rock bear up the lower members of the carboniferous deposit, while along the extended plateau on the south the yellow sandstone of the old red has been brought to the surface. The whole would thus seem to occupy the upraised floor of the great coal basin of Mid Lothian, dislocated and separated by the igneous matter of Arthur’s Seat and the Calton, whence the metals all plunge to the eastward.—The flat, extending from Restalrig toward Granton and Craigleith, consists of the same series of beds as those upon which the New Town stands, and which have been elevated by the dykes and bosses of trap that so frequently intersect the strata.