THE POPULAR SCIENCE MONTHLY.
|THE GREAT CEMETERY IN COLORADO.|
IN the composition of his ecclesiastical history, an erudite historian chaptered the narrative into centuries. Perhaps for his subject these divisions were sufficiently generous. Still, as measurements of time they were but puny epochs; and yet they were vast enough for the treatment of that ephemeral worker, man. But He, "who worketh hitherto"—who, as the true Earth's Biographer, wrote on the stony rocks—made his divisions the Ages! Indeed, can those epochs be reduced to years? What a scope must the record of his doings have with whom a thousand years are as a day! Accepting these life-cycles with a significance so grand, we reverently look into this great volume. Its opening chapter is the Cambrian age. But—amazing!—the stony laminæ that make up its leaves are scarcely less than one hundred thousand feet in thickness! It was a time of dreary wildness, and its primeval life-forms were few, and huge rock-masses were tilted up from that sea, and worn down for the bed of the waters. Next came the Silurian age, singing the weird music of its one world-encircling sea. Its forms of life were innumerable. Then flourished the Brachiopods, or shell-bearing worms, and Mollusca, Crustacea, corals, and a few fishes. Then comes the Devonian age. Now it is that what seemed a monotonous, watery waste becomes as a weary Sahara, with many a green-fringed oasis cheered. The late universal sea is dotted with low-lying islands. Very beautiful, though lowly in rank, and not over-luxuriant in numbers, were the plant-forms that fringed those shores. Then the fishes composed the nobility of life. Their patterns were grotesque; and they were clad in mighty plate-armor, massive osseous tiles, of quaintly sculpture. It was an armature that spoke unmistakably of crimson conflicts; for, in sooth, these were not "piping times of peace." Next came the Carboniferous age. The area of land is greatly increased; and it is beautified with a new and amazingly luxuriant vegetation. In this plant régime the queenliest being is the arborescent fern. And this luxuriant vegetation stores up the solar force, a rich legacy for the far-off but "coming man." At this time a few air-breathers occupy the land. "With frog-like affinities, they are of very low reptilian rank.
Passing the Permian and the Jurassic, next comes the Cretaceous age, with the culmination of that reptilian race of monsters of amazing size and most singular aspects. It was, indeed, the companionship of "Beauty and the Beast;" for at this time, also, the nautilus, and the ammonite, those peerless structures of the molluscan life, reveled in beauty and vastness of numbers. But a sad change came, and the gay nautilus tribe was reduced to the merest representation