eleme t, the solid, the earth, quitting the place its weight had assigned to it, rises from the bed of this boundless ocean; it lifts itself above the level of the waters, cuts the surface, puts itself in contact with the atmosphere, from which it had been separated by the whole thickness of the primeval ocean, and warms itself in the life-giving rays of the sun.

This fact of the appearance of the firm earth above the waters of the oceans, is an immense step in the rise and growth of the life of the globe. The three forms of matter react henceforth upon each other; the atmosphere, the seas, and the lands, absorbing the solar heat in an unequal manner, the ancient equilibrium is destroyed; the winds, the currents, are modified in their march; the climates are more varied; the rains become useful, and henceforth water and fertilize the land. Finally, a new element renders the appearance of a greatly superior organic life possible, and becomes the seat of a vegetation, and an animal world of a very different degree of perfection from that which existed before. It is a victory gained by higher life over matter, which it compels to serve a mɔre exalted end.

But geology demonstrates at in the earliest ages of the epoch of organic life on the earth, the organic epoch, as I would fain call it, the firm lands are reduced to a few islands only, scattered over the bosom of the

oceans.

"Apparent rari nantes in gurgite vasto."

Everywhere the beginnings are modest. The place of the future continents is not yet marked, except by

a few scattered stripes, forming here and there a few archipelagos. It is the insular epoch comprising all the earliest ages of geology You will see this by the two maps before you; the ne represents Europe at the Silurian epoch, the most ancient of the fossiliferous strata, and the other, North America at the Coal epoch, which, although a little more recent, belongs almost to the same age. (See Figs. 2 and 3.)

It is doubtless hardly necessary to state that such maps can only be approximations. They indicate sub

stantially those of the present dry lands which already existed at that time, and which have not been covered by the waters of the ocear. since those ancient epochs, except, perhaps, in the diluvian. But imperfect as are the data of geology, in this regard, the fact of the gradual increase of the dry lands is none the less placed beyond a doubt.

The largest domain, then, above the surface of the water, in the regions of the future continent of Europe, was Scandinavia, and a part of Russia. England and Scotland are only marked by a few islands along the existing western coast; Ireland, by a few others, placed at the corners of the present island. All France is represented merely by an island, corresponding to the central table land of Auvergne, and by some strips of land in Vendée, in Brittany, and in Calvados. In Germany, Bohemia forming a great island, the Harz, and the plateau of the Lower Rhine; small portions of the Vosges, and of the Black Forest, and some low lands on the spot occupied by the Alps, between Toulon, Milan and Tyrol, compose an archipelago which is to become the centre of the continent. All the regions of the South, except, perhaps, a few small portions of Spain and of Turkey, do not yet exist.

North America, at the epoch when the coal deposits are formed, is, in like manner, made up of a few islands only, analogous to Scandinavia, but less numerous, less parcelled out than we find them in Europe at the same period. A large island occupies all the present northeast of the continent, with the region of the Alleghanies and the Apalachian, and all the region north-west of the

Valley of the Mississippi, and forms a species of small continent, in the interior of which are three large inland seas, or three large swamps, where the plants are vegetating that compose the great coal deposits of the present day. A similar sea doubtless lay between Nova Scotia and Newfoundland, bordered, perhaps, by lands which have disappeared beneath the waves. All the great belt of low lands along the Atlantic coast and the Gulf of Mexico, including Florida, did not exist; the ocean formed a deep gulf, running up the Valley of the Mississippi one half its length.

The vast plains west of the Mississippi, the Rocky

Mountains, the table lands and the high snow-capped chains from California to the Frozen Ocean, were still at the bottom of the sea.

This augmentation of the number of the islands, their clustering in archipelagos, is certainly a progress; there is still, however, but little variety; the mountains are few in number, and slightly elevated; the valleys traced but indistinctly or not at all; the slopes imperfectly determined; extensive low and swampy regions indicate still the preponderance of the watery element. A thicker and denser atmosphere equalizes the temperatures. One species of climate alone, the maritime or insular climate, moist, without extremes, reigns over land and sea. No great continents, none of those elevated masses which give to climate extreme and variable temperatures, and the character of dryness; none of all those varied forms of vegetation which show themselves later under its influences.

The organized beings corresponding to this physical condition of the surface of the globe, show with the utmost clearness this character of uniformity and inferiority. From one extremity of the earth to the other, the Trilobites of the Silurian epoch are found identical in · their species, at once in America, in Europe, in Africa, and in New Holland. The vegetables, accumulated in the coal beds, are the same at the poles and the equator. The types of organized beings are not only few in number, but they all still belong to those which mark the inferior degrees of animal life; and in each class, from the radiates to the fishes, the highest beings of this primitive creation, the prevailing forms are those