The mountain limestone of our own country, formed in like manner on the sea-bottom of corallines, has a wide geographical range, extending from the bay of St. Andrew’s on the north, to the extremity of Wales on the south; passing into Ireland, where it is elevated into long ridges, or occupies the mountain-slopes; and forming outliers or extended barriers in all the southern counties of Scotland, and in the greater portion of the northern, the middle, and the south-western districts of England. These were the coral reefs of an ocean now raised into dry land, divided, too, into outer and inner compartments, or arranged into systems of lines and branches, which diverged from or inosculated with each other. Nor does the resemblance between the recent and the more ancient formations stop here, but extends to the structure of the deposits, lithologically considered, the mechanical, sub-crystalline, and crystalline texture being exhibited in both sets of rocks. Thus, in the examination of Heron Island, the coral beds, one to two feet thick, are found to have a tendency to split into slabs, and joints are observed to cross each other at right angles, parallel to the dip and strike, respectively, giving to the still living coral rock the jointings, cleavage, and stratification of the greater palæozoic deposits. Naturalists divide these polyps into existing and extinct races. But whether extinct and specifically different, or otherwise, they are creatures of a family, possessed of the same habits and performing the same operations, now as of old; and if, as geologists say, millions of ages have elapsed between the actings of the first and last generations, our admiration will be only all the more unbounded by thus witnessing the harmony of creation through indefinite time, and the accuracy of the Book which contains the record of it.