Some of the scientists, ciphering out the evidence furnished by geology, have arrived at the conviction that the world is prodigiously old. Lord Kelvin doesn't agree with them. He says that it isn't more than a hundred million years old, and he thinks the human race has inhabited it about thirty thousand years of that time. Even so, it was 99,970,000 years getting ready, impatient as the Creator doubtless was to see man and admire him. That was because God first had to make the oyster. You can't make an oyster out of nothing, nor you can't do it in a day. You've got to start with a vast variety of invertebrates, belemnites, trilobites, jebusites, amalekites, and that sort of fry, and put them into soak in a primary sea and observe and wait what will happen. Some of them will turn out a disappointment; the belemnites and the amalekites and such will be failures, and they will die out and become extinct in the course of the nineteen million years covered by the experiment; but all is not lost, for the amalekites will develop gradually into encrinites and stalactites and blatherskites, and one thing and another, as the mighty ages creep on and the periods pile their lofty crags in the primordial seas, and at last the first grand stage in the preparation of the world for man stands completed; the oyster is done. Now an oyster has hardly any more reasoning power than a man has, so it is probable this one jumped to the conclusion that the nineteen million years was a preparation for him. That would be just like an oyster, and, anyway, this one could not know at that early date that he was only an incident in a scheme, and that there was some more to the scheme yet.
"The oyster being finished, the next step in the preparation of the world for man was fish. So the old Silurian seas were opened up to breed the fish in. It took twenty million years to make the fish and to fossilize him so we'd have the evidence later.
"Then, the Paleozoic limit having been reached, it was necessary to start a new age to make the reptiles. Man would have to have some reptiles-- not to eat, but to develop himself from. Thirty million years were required for the reptiles, and out of such material as was left were made those stupendous saurians that used to prowl about the steamy world in remote ages, with their snaky heads forty feet in the air and their sixty feet of body and tail racing and thrashing after them. They are all gone now, every one of them; just a few fossil remnants of them left on this far-flung fringe of time.
"It took all those years to get one of those creatures properly constructed to proceed to the next step. Then came the pterodactyl, who thought all that preparation all those millions of years had been intended to produce him, for there wasn't anything too foolish for a, pterodactyl to imagine. I suppose he did attract a good deal of attention, for even the least observant could see that there was the making of a bird in him, also the making of a mammal, in the course of time. You can't say too much for the picturesqueness of the pterodactyl --he was the triumph of his period. He wore wings and had teeth, and was a starchy-looking creature. But the progression went right along.
"During the next thirty million years the bird arrived, and the kangaroo, and by and by the mastodon, and the giant sloth, and the Irish elk, and the old Silurian ass, and some people thought that man was about due. But that was a mistake, for the next thing they knew there came a great ice-sheet, and those creatures all escaped across the Bering Strait and wandered around in Asia and died, all except a few to carry on the preparation with. There were six of those glacial periods, with two million years or so between each. They chased those poor orphans up and down the earth, from weather to weather, from tropic temperature to fifty degrees below. They never knew what kind of weather was going to turn up next, and if they settled any place the whole continent suddenly sank from under them, and they had to make a scramble for dry land.