round its axis, and become solid at its surface by the slow dissipation of its heat or other causes, would assume.  I suppose, therefore, that the globe, in the first state in which the imagination can venture to consider it, was a fluid mass with an immense atmosphere revolving in space round the sun, and that by its cooling a portion of its atmosphere was condensed in water which occupied a part of the surface.  In this state no forms of life such as now belong to our system could have inhabited it; and, I suppose, the crystalline rocks (or, as they are called by geologists, the primary rocks), which contain no vestiges of a former order of things, were the results of the first consolidation on its surface.  Upon the further cooling the water which more or less had covered it contracted, depositions took place, shell-fish and coral insects of the first creation began their labours, and islands appeared in the midst of the ocean raised from the deep by the productive energies of millions of zoophytes.  Those islands became covered with vegetables fitted to bear a high temperature, such as palms and various species of plants similar to those which now exist in the hottest parts of the world; and the submarine rocks or shores of these new formations of land became covered with aquatic vegetables, on which various species of shell-fish and common fishes found their nourishment.  The fluids of the globe in cooling deposited a large quantity of the materials they held in solution, and these deposits agglutinating together the sand, the immense masses of coral rocks, and some of the remains of the shells and fishes found round the shores of the primitive lands, produced the first order of secondary rocks.  As the temperature of the globe became lower, species of the oviparous reptiles were created to inhabit it; and the turtle, crocodile, and various gigantic animals of the sauri kind, seem to have haunted the bays and waters of the primitive lands.  But in this state of things there was no order of events similar to the present; the crust of the globe was exceedingly slender, and the source of fire a small distance from the surface.  In consequence of contraction in one part of the mass, cavities were opened, which caused the entrance of water, and immense volcanic explosions took place, raising one part of the surface, depressing another, producing mountains, and causing new and extensive depositions from the primitive ocean.  Changes of this kind must have been extremely frequent in the early epochas of nature, and the only living forms of which the remains are found in the strata that are the monuments of these changes, are those of plants, fishes, birds, and oviparous reptiles, which seem most fitted to exist in such a war of the elements.  When these revolutions became less frequent, and the globe became still more cooled, and the inequalities of its temperature preserved by the mountain chains, more perfect animals became its inhabitants, many