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Each wrought alone, yet altogether wrought
Unconscious, not unworthy instruments,
By which a hand invisible was rearing

A new creation in the secret deep.

Omnipotence wrought in them, with them, by them,
Hence what alone Omnipotence alone could do,
Worms did. I saw the living pile ascend-

The mausoleum of its Architects

Still dying upwards as their labours closed.
Slime the material, but the slime was turned
To adamant by their petrific touch.

Frail were their frames, ephemeral their lives,
Their masonry imperishable."

On islands so formed, the sea bird finds a resting-place when wearied fishing-the waves deposit floating wreck, animal and vegetable-the winds and waves bring seedsthe land birds too contribute their share of seeds undigested in their stomachs-and both land and sea birds contribute fertilizing guano. The island in time becomes covered with grass and shrub and tree; animals reach it, unwilling navigators, blown from the land on some tree or floating branch; and lastly, man arrives in his canoe, mayhap also an unwilling voyager, or a voluntary exile seeking for himself and family a shelter from persecution, or the murderous attacks of savage enemies.

Three inhabitants of Tahiti had their canoe drifted to the island of Wateroo, a distance of 550 miles, and Malte Brun relates that, in 1696, two canoes, containing thirty persons, were thrown by storm and contrary winds upon one of the Phillippines, 800 miles from their own islands. Kotzebue also states that, in one of the Caroline islands, he became acquainted with Kadu, a native of Ulea. Kadu,

with three of his countrymen, left Ulea in a sailing boat for a day's excursion, when a violent storm arose and drove them out of their course. For eight months they drifted about in the open sea, according to their reckoning by the moon, making a knot on a cord at every new moon. Being expert fishermen, they were able to maintain themselves by the produce of the sea, and caught the falling rain in some vessels that were on board. Kadu, being a diver, frequently went down to the bottom, where it is well known that the water is not so salt, taking a shell with only a small opening to receive a supply. When these castaways at last drew near to land, every hope and almost every feeling had died within them; but, by the care of the islanders of Aus, they were soon restored to perfect health. Their distance from home in a direct line was 1500 miles. Such are some of the means whereby islands have been raised from the ocean, covered with soil, and become inhabited.

Through all nature we recognize fixed laws, and behold the conditions under which they act, and to some extent the effect produced. We can thus form some idea of their operations in the past ages of the world, and arrive at the conclusion that immense periods of time must have been consumed in the gradual changes exhibited to us in the geologic record. But, although the laws are the same and fixed, the conditions are varying. The laws of crystallization, light, heat, meteorology, and the great principles of animal and vegetable physiology, are the same now as at the beginning, mayhap hundreds of millions of years ago. The conditions, however, under which the laws are exerted may vary, and have done so.

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Where now are the poles of the earth-where there is almost perpetual frost and snow-there once abounded a rich tropical vegetation similar to that of India and Africa at the present day. This is proved by the fossil remains of trees, shrubs, and animals, habitants of a warm climate. Some have attempted to account for this by a decrease of the internal heat, and consequently of the temperature, on the surface. But plants require light as well as heat, and whilst the earth occupies its present fosition towards the sun, there must be always darkness for about three months at the poles, sufficient reason to account for the absence of prolific vegetation beyond the arctic circle at the present day. The truth is, the orbit of the earth is variable. The slightest change will cause the sun's rays to fall upon the earth differently, and yet be sufficient to produce a marked change on its surface. The earth has another motion than those ascribed to it by astronomers, very slow, but still certain, so that not only is the earth subject to changes from dry land to sea bottom, but the poles have been the tropics, or at least subjected to the action of the sun's rays as in the tropics. The great sothic seasons of the earth have changed, and with them the animal and vegetable productions. What an idea of time past does this present in the history of the earth!

In addition to these causes for geological change, always in action, man has, during his brief sojourn upon earth's surface, largely aided both involuntarily and by design. In death, his remains mingle with and swell the superficial earth soil. In life, the stony strata are made to minister to his comfort and daily use in the building of cities, temples, bridges, and other works of civilization, and in the abstrac

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tion of ores and fuel from the bowels of the earth for purposes of commerce and art. Forests are cut down, swamps drained, land reclaimed, affecting the climate and physical character of a country; and land cultivated or reclaimed from the grasp of the ocean, introduces a new flora, and spread of leguminous and cereal plants, and the supplanting of wild animals by domestic varieties. How different the condition of Britain from the time when Cæsar landed his cohorts on its coasts—abounding in forests and morasses, tenanted by the bear, the wolf, and the fierce bison; and, within a more limited period, how great the alteration across the Atlantic, in America, since the landing of the Pilgrim Fathers from the little "May Flower" on the shores of Masachussets.

Still, the great laws of nature remain unchanged. The first crystal formed was formed exactly with the same angles, and in the same shape as the last; the first clouds of vapour that rose into the air, and again fell in drops of rain, did so like the shower of to-day; the first rushing wind that swept the ocean restored the equilibrium exactly like the cyclone which has passed, or the gale which has made its circuit round our coasts; the first leaf that fell on the earth, the first river that ran into the sea, obeyed the same laws of gravitation which are in operation at this hour. The races of animals and plants, which have lived and died, have changed their forms, but the same identical laws which guide them now guided them in the past.

CHAPTER III.

THE changes which have occurred during comparatively modern periods, and which can be proved by distinct evidence, will give some slight indications of the time necessary to produce certain effects.

Says Professor Philips, "The geological scale of time is founded on the series of the strata deposited in the ancient sea; if the forces tending to produce such deposits have always been productive of equal effects in equal times, the thicknesses of the strata are exact measures of the times. The thickness, added in a certain historical time to the modern sea bed, will bear the same proportion to the total thickness, which has been added in geological time, as the historical time ascertained to the geological time required. For example, assume an extravagantly high rate of waste, such as that on the coasts of England, which certainly cannot equal one foot in a year; apply it to the whole of the sea coasts of the world; assume these to be equal to four circuits of the globe, that is to say, 100,000 miles in extent, and 100 feet high. The annual waste will be (100,000 x 100 x 1) ÷ 5280o 0'4 cubic miles of sediment. The area of the land being, as before assumed, equal to the area of new deposits, we have 50,000,000 square miles covered one 2000th inch deep with these spoils won by the sea from the land.”

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