I. THE GEOGRAPHICAL DISTRIBUTION OF THE COAL METALS.—Our knowledge on this subject is increasing with every new geographical detail connected with the history of the earth. Until very recently the carboniferous system was supposed to be of very limited extent. The return of every vessel, engaged in a voyage of discovery or otherwise, brings tidings of some new island or continent on which it is found. The same tribes of plants and animals are everywhere observed to accompany the deposit—all presenting the same generic and often the same specific characters—and uniformly on the same great scale of development. This circumstance alone bespeaks a universal formation, when every region was capable of producing all the requisite conditions in climate, vegetables, corallines, and sea-bottom, and prepares the mind for the ready admission of the existence of the mineral in every unexplored quarter of the globe. Accordingly, all the great continents of the old world abound in coal. In Russia, the carboniferous system occupies, betwixt the Dnieper and the Don, an area of about eleven thousand square miles. India, China, and the Australian archipelago give up yearly more and more of the bituminous substance. Egypt is not destitute of the jetty mineral: for recently beds several feet thick have been discovered near Asuan, on the right bank of the Nile. The vast continent of America has it in proportion to its own vastness. And man, go where he will with the knowledge of the arts, and the diffusive blessings of religion and civilization, will always find that a wise Providence has anticipated his wants, and prepared the treasure for his use. The coal formation in Scotland has been already traced as occupying the great central valley of the Lowlands, which separates the primitive crystalline and feldspathic rocks of the north from the silurian series of the southern border, and traversing the mainland from sea to sea. The middle and northern coal basins of England have an average uninterrupted stretch of about two hundred miles in length, by forty in breadth. The Bristol and Welsh coal-fields, are also very extensive. That of South Wales forms an immense double trough, comprised within a great oval elongated tract, betwixt St. Bride’s Bay, and Pontypool, with an anticlinal axis ranging east and west, and embracing an area of one thousand and fifty-five square miles. This is the largest coal-field in Britain, in which there are sixty-four seams of coal, of all qualities, from the highest bituminous to the purest anthracite, and having an aggregate thickness of one hundred and ninety-feet. In Ireland the coal basins are comparatively small, and isolated from one another: the principal workable seams are in the counties of Kilkenny, Tipperary, Cork, Tyrone, and the northern extremity of Roscommon.