Fig. 1. Diagram illustrating Folding of the Crust of the Earth.—(a) Undisturbed crust. (b) Primary depression and deposition. (c) Mountain-making folds with their relations to an upper and lower magma.
Fig. 2. Result of folding, faulting, and denudation, as seen at Cascade Mountain, Western Canada
(after McConnell, p. 33).
[CHAPTER II.]
WORLD-MAKING.
G
Geological reading, especially when of a strictly uniformitarian character and in warm weather, sometimes becomes monotonous; and I confess to a feeling of drowsiness creeping over me when preparing material for a presidential address to the American Association for the Advancement of Science in August, 1883. In these circumstances I became aware of the presence of an unearthly visitor, who announced himself as of celestial birth, and intimated to me that being himself free from those restrictions of space and time which are so embarrassing to earthly students, he was prepared for the moment to share these advantages with me, and to introduce me to certain outlying parts of the universe, where I might learn something of its origin and early history. He took my hand, and instantly we were in the voids of space. Turning after a moment, he pointed to a small star and said, "That is the star you call the sun; here, you see, it is only about the third magnitude, and in a few seconds it will disappear." These few seconds, indeed, reduced the whole visible firmament to a mere nebulous haze like the Milky Way, and we seemed to be in blank space. But pausing for a moment I became aware that around us were multitudes of dark bodies, so black that they were, so to speak, negatively visible, even in the almost total darkness around. Some seemed large and massive, some a mere drift of minute particles, formless and without distinct limits. Some were swiftly moving, others stationary, or merely revolving on their own axes. It was a "horror of great darkness," and I trembled with fear. "This," said my guide, "is what the old Hebrew seer called tohu ve bohu, 'formless and void,' the 'Tiamat' or abyss of the old Chaldeans, the 'chaos and old night' of the Greeks. Your mundane physicists have not seen it, but they speculate regarding it, and occupy themselves with questions as to whether it can be lightened and vivified by mere attractive force, or by collision of dark bodies impinging on each other with vast momentum. Their speculations are vain, and lead to nothing, because they have no data wherefrom to calculate the infinite and eternal Power who determined either the attraction or the motion, or who willed which portion of this chaos was to become cosmos, and which was to remain for ever dead and dark. Let us turn, however, to a more hopeful prospect." We sped away to another scene. Here were vast luminous bodies, such as we call nebulæ. Some were globular, others disc-like, others annular or like spiral wisps, and some were composed of several concentric shells or rings. All were in rapid rotation, and presented a glorious and brilliant spectacle. "This," said my guide, "is matter of the same kind with that we have just been considering; but it has been set in active motion. The fiat 'Let there be light!' has been issued to it. Nor is its motion in vain. Each of these nebulous masses is the material of a system of worlds, and they will produce systems of different forms in accordance with the various shapes and motions which you observe. Such bodies are well known to earthly astronomers. One of them, the great nebula of Andromeda, has been photographed, and is a vast system of luminous rings of vapour placed nearly edgewise to the earth, and hundreds of times greater than the whole solar system. But now let us annihilate time, and consider these gigantic bodies as they will be in the course of many millions of years." Instantaneously these vast nebulæ had concentrated themselves into systems of suns and planets, but with this difference from ours, that the suns were very large and surrounded with a wide luminous haze, and each of the planets was self-luminous, like a little sun. In some the planets were dancing up and down in spiral lines. In others they were moving in one plane. In still others, in every variety of direction. Some had vast numbers of little planets and satellites. Others had a few of larger size. There were even some of these systems that had a pair of central suns of contrasting colours. The whole scene was so magnificent and beautiful that I thought I could never weary of gazing on it. "Here," said he, "we have the most beautiful condition of systems of worlds, when considered from a merely physical point of view: the perfection of solar and planetary luminousness, but which is destined to pass away in the interest of things more important, if less showy. This is the condition of the great star Sirius, which the old priest astronomers of the Nile Valley made so much of in their science and religion, and which they called Sothis. It is now known by your star-gazers to be vastly larger than your sun, and fifty times more brilliant.[1] Let us select one of these systems somewhat similar to the solar system, and suppose that the luminous atmospheres of its nearer planets are beginning to wane in brilliancy. Here is one of them, through whose halo of light we can see the body of the planet. What do you now perceive?" The planet referred to was somewhat larger in appearance than our earth, and, approaching near to it, I could see that it had a cloud-bearing firmament, and that it seemed to have continents and oceans, though disposed in more regular forms than on our own planet, and with a smaller proportion of land. Looking at it more closely, I searched in vain for any sign of animal life, but I saw a vast profusion of what might be plants, but not like those of this world.[2] These were trees of monstrous stature, and their leaves, which were of great size and shaped like fronds of seaweeds, were not usually green, but variegated with red, crimson and orange. The surface of the land looked like beds of gigantic specimens of Colias and similar variegated-leaved plants, the whole presenting a most gorgeous yet grotesque spectacle. "This," said my guide, "is the primitive vegetation which clothes each of the planets in its youthful state. The earth was once so clothed, in the time when vegetable life alone existed, and there were no animals to prey upon it, and when the earth was, like the world you now look upon, a paradise of plants; for all things in nature are at first in their best estate. This vegetation is known to you on the earth only by the Carbon and Graphite buried in your oldest rocks. It still lingers on your neighbour Mars,[3] which has, however, almost passed beyond this stage, and we are looking forward before long to see a still more gigantic though paler development of it in altogether novel shapes on the great continents that are being formed on the surface of Jupiter. But look again." And time being again annihilated, I saw the same world, now destitute of any luminous envelope, with a few dark clouds in its atmosphere, and presenting just the same appearance which I would suppose our earth to present to an astronomer viewing it with a powerful telescope from the moon. "Here we are at home again," said my guide; "good-bye." I found myself nodding over my table, and that my pen had just dropped from my hand, making a large blot on my paper. My dream, however, gave me a hint as to a subject, and I determined to devote my address to a consideration of questions which geology has not solved, or has only imperfectly and hypothetically discussed.
[1] In evidence of these and other statements I may refer to Huggins' recent address as President of the British Association, and to the "Story of the Heavens," etc., by Sir Robert Ball.
[2] We shall see farther on that there is reason to believe that the primitive land vegetation was more different from that of the Devonian and Carboniferous than it is from that of the present day.
[3] Mars is probably a stage behind the earth in its development, and the ruddy hue of its continents would seem to b: due to some organic covering.