thoughts. “Smell that sulphur? If this place wasn't once the scene of volcanic activities, I'm no judge!”
A moderate yet very steady wind blew upward from the chasm, freighted with a scent of sulphur and some other substance new to Stern.
Beatrice, all at once overcome by sudden giddiness, drew back and hid her face in both hands.
“No bottom to it--no end!” she said in a scared tone. “Here's the end of the world, right here, and beyond this very rock--nothing!”
Stern, puzzled, shook his head.
“That's really impossible, absurd and ridiculous, of course,” he answered. “There
He pitched a two-pound lump of granite far out into the air. It fell vertically, whirling, and vanished with the speed of a meteor.
“If a whole side of the earth had split off, and what we see down below there were really sky, of course the earth's center of gravity would have shifted,” he explained, “and that rock would have fallen in toward the cliff below us, not straight down.”
“How can you be sure it doesn't fall that way after the impulse you gave it has been lost?”
“I shall have to make some close scientific tests here, lasting a day or two, before I'm positive; but my impression is that this, after all, is only a canon--a split in the surface--rather than an actual end of the crust.”
“But if it were a canon, why should blue sky show down there at an angle of forty-five degrees?”
“I'll have to think that out, later,” he replied. “Directly under us, you see all seems deep purple. That's another fact to consider. I tell you, Beatrice, there's more to be figured out here than can be done in half an hour.
“As I see it, some vast catastrophe must have rent the earth, a thousand or fifteen hundred years ago, as a result of which everybody was killed except you and me. We're standing now on the edge of the scar left by that explosion, or whatever it was. How deep or how wide that scar is, I don't know. Everything depends on our finding out, or at least on our guessing it with some degree of accuracy.”
“How so?”
“Because, don't you see, this chasm stands between us and Chicago and the West, and all our hopes of finding human life there. And--”
“Why not coast south along the edge here, and see if we can't run across some ruined city or other where we can refill the tanks?”
“I'll think it over,” the engineer answered. “In the meantime we can camp down here a couple of days or so, and rest; and I can make some calculations with a pendulum and so on.”
“And if you decide there's probably another side to this gulf, what then?”
“We cross,” he said; then for a while stood silent, musing as he peered down into the bottomless abyss that stretched there hungrily beneath their narrow observation-rock.
“We cross, that's all!”
CHAPTER XXI. LOST IN THE GREAT ABYSS
For two days they camped beside the chasm, resting, planning, discussing, while Stern, with improvised transits, pendulums and other apparatus, made tests and observations to determine, if possible, the properties of the great gap.
During this time they developed some theories regarding the catastrophe which had swept the world a thousand years ago.
“It seems highly and increasingly probable to me,” the engineer said, after long thought, “that we have here the actual cause of the vast blight of death that left us two alone in the world. I rather think that at the time of the great explosion which produced this rent, certain highly poisonous gases were thrown off, to impregnate the entire atmosphere of the world. Everybody must have been killed at once. The poison must have swept the earth clean of human life.”
“But how did
“That's hard telling. I figure it this way: The mephitic gas probably was heavy and dense, thus keeping to the lower air-strata, following them, over plain and hill and mountain, like a blanket of death.
“Just what happened to us, who can tell? Probably, tightly housed up there in the tower, the very highest inhabited spot in the world, only a very slight infiltration of the gas reached us. If my theory won't work, can you suggest a better one? Frankly, I can't; and until we have more facts, we've got to take what we have. No matter, the condition remains--we're alive and all the rest are dead; and I'm positive this cleft here is the cause of it.”
“But if everybody's dead, as you say, why hunt for men?”
“Perhaps a handful may have survived among the highlands of the Rockies. I imagine that after the first great explosion there followed a series of terrible storms, tornadoes, volcanic eruptions, tidal waves and so on. You remember how I found the bones of a whale in lower Broadway; and many of the ruins in New York show the action of the sea--they're laid flat in such a manner as to indicate that the island was washed on one or two occasions by monster waves.
“Well, all these disturbances probably finished up what few survivors escaped, except possibly among the mountains of the West. A few scattered colonies may have survived a while--mining camps, for instance, or isolated prospectors, or what-not. They may all have died out, or again, they may have come together and reestablished some primitive form of barbarous or even savage life by this time. There's no telling. Our imperative problem is to reach that section and explore it thoroughly. For there, if anywhere, we'll find survivors of our race.”
“How about that great maelstrom that nearly got us?” asked the girl.” Can you connect that with the catastrophe?”
“I think so. My idea is that, in some way or other, the sea is being sucked down into the interior of the earth and then hurled out again; maybe there's a gradual residue being left; maybe a great central lake or sea has formed. Who knows? At any rate all the drainage system of the country seems to have been changed and reversed in the most curious and unaccountable manner. I think we should find, if we could investigate everything thoroughly, that this vast chasm here is intimately connected with the whole thing.”
These and many other questions perplexed the travelers, but most of all they sought to know the breadth of the vast gap and to determine if it had, as they hoped, another side, or if it were indeed the edge of an enormous mass split bodily off the earth.
Stern believed he had an answer to this problem on the afternoon of the second day. For many hours he had hung his pendulums over the cliff, noted deflections, taken triangulations, and covered the surface of the smooth stone with X's, Y's, Z's, sines and cosines and abstruse formulae--all scrawled with charcoal, his only means of writing.
At last he finished the final equation, and, with a smile of triumph and relief, got to his feet again.
Back to the girl, who was cooking over an odorous fire of cedar, he made his way, rejoicing.
“I've got it!” he shouted gladly. “Making reasonable allowances for depth, I've got it!”
“Got what?”
“The probable width!”
“Oh!” And she stood gazing at him in admiration, beautiful and strong and graceful. “You mean to say--”
“I'm giving the chasm a hundred miles' depth. That's more than anybody could believe possible--twice as much. On that assumption, my tests show the distance to the other side--and there is another side, by the way!-- can't be over--”
“Five hundred miles?”
“Nonsense! Not over one hundred to one-fifty. I'm going on a liberal allowance for error, too. It may not be over seventy-five. The--”
“But if that's as far as it is, why can't we see the other side?”
“With all that chemicalized vapor rising constantly? Who knows what elements may be in it? Or what polarization may be taking place?”
“Polarization?”
