CHAPTER XXVII.

METHOD IN THE GROWTH OF CONTINENTS.

HOV

OW impressive the unity of purpose with which Nature has pushed forward the consummation of her vast schemes! Ends have been foreshadowed through almost an eternity of years, while the all-directing Mind has steadily controlled the ministering forces, in the midst of millions of disturbing agencies, till the premeditated work has been accomplished. We witness in the plans of the Infinite Architect the same intelligent cohesion of parts as in a well-laid human scheme; and while the relations of certain events far transcend the scope of our reason, and the perfection of contrivance is immeasurably superior to that of human designs, we understand enough and measure enough to know that a philosophy which is at once human in its method and divine in its comprehension underlies the whole chain of natural events. There is a logical relationship of things established by God and recognizable by man, and the sequences of events are ofttimes so clear that even finite intelligence is able to penetrate the future and unveil plans existing only in the Infinite conception.

This ideal connection of the parts of the Creator's universe is, perhaps, best traced among organized beings, but I propose first to point out its existence in the history of inorganic nature. The infinitely diversified features of the earth's surface have been wrought out by the operation of a few principles working through ages in definite modes. We see that certain rocks bear the evidences of their sedimentary origin. We look about, and find sedimentary ac

cumulations still forming and hardening. We look back, and ascertain that the same processes, continued through ages of the past, have piled up thousands of feet of rocky beds, in which still slumber the mummied forms of the primeval world. We see that certain rocks bear the marks of fire. We plunge our hands into a thermal spring, and gather intimations of internal heat. The molten eructations of a volcano demonstrate the continued existence of melted rocks. If masses of igneous origin have cooled from a state of fusion, who can say that they have not cooled from that higher temperature at which we know that rocks and all other things can subsist only as vapor? Do we find rocks existing in that condition? Yes; worlds still exist as igneous vapors. Here, then, we may assume our starting-point. A world of airy flame, after ages of cooling, gathered a liquid nucleus at its core-a globe of molten rock, wrapped in a glowing atmosphere of all that remained as vapor. Next, a fiery floor congeals over the surface of the burning tide; the burning tide, as if in rage, lashes it to fragments, and the abated heat allows them to be recemented. When the hotter fires had been quite imprisoned in the strengthening crust, dews began to gather in the upper air, and streaks of haze barred out the burning beams of the lurid sun. Rains fell upon the fervid crust, to waste themselves in sudden vapor, and return to the attack upon the crust. Gleams of electricity lighted the misty drapery of this geologic night, while the thunders of Nature's ordnance echoed through the caverns of the clouds.

A rain of acid waters at length got the mastery of the wrinkled surface, and every ravine and valley witnessed the race of the rivers for the lowest levels. Every watercourse bore onward its freight of sediment, the materials of the masonry of continents. The filmy ocean swallowed

the rivulet, crawled over the hill-top, and embraced the world. The world, in turn, opened its wide and rocky jaws and swallowed the ocean-and another ocean laved the face of Nature.

In the progress of events, an occasional ridge of barren granite lifted its back permanently above the level of the sea. As the liquid core contracted, the surplusage of the enveloping crust was absorbed by the wrinkles already existing, and thus the granite backs rose higher and higher. As the ridges were higher raised, and the valleys deeper sunken, the accumulated oceans pressed heavier and heavier against the slopes of the rocky beds, and the gathered sediments of ages weighted the ocean's floor with a burden which easily outweighed the crust which bridged the hills. And thus it was that the valleys were ever deeper sunken, and that which was at first an insignificant wrinkle became at last a stable mountain. From the coast of Labrador southwest along the Laurentian Hills we tread upon that ancient summit which was the first-born of Old Ocean. From the far northwest it comes down to us with the same time-worn record written on its weathered brow, while a chain of noble lakes fringes the angulated ridge along its western branch, and the eastern bathes its feet in the waters of the St. Lawrence. As the flowers of one spring-time foretell the forms which will reappear when spring-time comes again, so this ancient germinal ridge was but the first blooming of a continent; and when the circle of a geologic year was run, the rocky leaves of the growing continent unfolded themselves again in their appointed fashion. Note the parallelism of that primeval ridge with the present shores of the Atlantic and Pacific. When we know that each successive revolution of the globe has but rolled the waters of the oceans farther to the southeast and southwest, do we not perceive that the

deep ocean's bed has ever been the deep ocean's bed, and that the first ridge of land was the nucleus of the continent, and the trend of its shores a prophecy of the coastlines of our day?

Here, then, immeasurable ages before the creation of man-before even a living thing had crawled in the waters of the sea-Nature had distinctly staked out the birthplace of American freedom, and fenced in one inclosure the vast area between the Atlantic and the Pacific-between the great lakes and the Mexican Gulf and forebore to raise a single separating barrier from one extreme of the empire of freedom to the other. And, through all the chances of following revolutions, she has never erected an Alpine boundary to thwart her purpose in the unity of the continent.

By successive upheavals belt after belt was added to the area of the land. Even a phase of continental history which seems somewhat exceptional was wrought out by the strictest adherence to the established methods. When the time arrived for the creation of land animals, the shrinkage of the nucleus had proceeded to a point which subjected the crust to the most enormous lateral pressures. Uneasy in every attitude, it maintained a perpetual oscillation-I say perpetual, though in movements so vast a hundred years are as a moment. Vegetation, which was appointed the scavenger of the atmosphere, gathered up its freight of carbon, and a well-timed subsidence of the surface inundated the carbonaceous accumulation, and buried it in mud and sand far from the reach of the destroying influence of the atmosphere. A hundred times the process was repeated; and so it happened that when the atmosphere was purified, the tension of the crust could be no longer borne, and one grand convulsion rolled up the Appalachians in their hundred folds; and there, nicely assort

ed between the rocky leaves of the mountains, were the layers of carbon, changed from the poison to the comfort. of the coming man!

To recount the events of the following ages is to repeat the story of the past. By-and-by the plastic hand of Nature had moulded the continent to its destined features. It seemed to need but man to be a finished work. But the Creative Architect contemplated a higher finish than human wisdom could have contrived. Now that the Atlantic and Pacific had completed those portions of the continent in their more immediate vicinage, it remained for the smaller sea which surrounds the pole to develop by its pressures the northern slope of the land, and thus to become the remote agent in strewing the surface of the rocks with an arable soil. The uplift of the arctic regions. brought on the reign of ice, and wintry devastation swept over the late verdant landscapes. The downthrow of the Arctic highlands ameliorated the climate, and Spring again visited the icy fields. The movements of ice and water left the surface covered with cubic miles of rubbish produced from the destruction of the underlying rocks. But the entire continent was destined to a new baptism. The once forbidden ocean was readmitted to career in triumph over states that had long ago been reclaimed from his dominion. Michigan disappeared beneath the wave, and Ohio, and Pennsylvania, and New York, and Canada. The entire northern and middle regions of the continent. sank down to a level lower than had been reached since the deposition of the coal. Then, in due time, began the last resurgence of the land. By degrees the finny waters shrunk back nearly to their former lines. Now the river channels were dug out; and now the Niagara began anew to plow its stupendous gorge. Unknown ages passed, and man assumed the sceptre of the earth.