“Over that edge,” said Knight, “where nothing but vacancy appears, is a moving compact mass. The wind strikes the face of the rock, runs up it, rises like a fountain to a height far above our heads, curls over us in an arch, and disperses behind us. In fact, an inverted cascade is there—as perfect as the Niagara Falls—but rising instead of falling, and air instead of water. Now look here.”
Knight threw a stone over the bank, aiming it as if to go onward over the cliff. Reaching the verge, it towered into the air like a bird, turned back, and alighted on the ground behind them. They themselves were in a dead calm.
“A boat crosses Niagara immediately at the foot of the falls, where the water is quite still, the fallen mass curving under it. We are in precisely the same position with regard to our atmospheric cataract here. If you run back from the cliff fifty yards, you will be in a brisk wind. Now I daresay over the bank is a little backward current.”
Knight rose and leant over the bank. No sooner was his head above it than his hat appeared to be sucked from his head—slipping over his forehead in a seaward direction.
“That’s the backward eddy, as I told you,” he cried, and vanished over the little bank after his hat.
Elfride waited one minute; he did not return. She waited another, and there was no sign of him.
A few drops of rain fell, then a sudden shower.
She arose, and looked over the bank. On the other side were two or three yards of level ground—then a short steep preparatory slope—then the verge of the precipice.
On the slope was Knight, his hat on his head. He was on his hands and knees, trying to climb back to the level ground. The rain had wetted the shaly surface of the incline. A slight superficial wetting of the soil hereabout made it far more slippery to stand on than the same soil thoroughly drenched. The inner substance was still hard, and was lubricated by the moistened film.
“I find a difficulty in getting back,” said Knight.