Not a word passed between the occupants of her wheelhouse.
Each was anxiously looking for an opening, even the cool-blooded Yankee being somewhat concerned at this deadlock.
As the moments went by without their hopes being realised, a fit of gloomy depression swept over them all, which was lifted at length, as a sharp cry broke from Seymour.
“Look!”
The submarine had crept round a great out-jutting spur of the ice-cliffs, and before her, in the face of the glittering wall, loomed a monstrous archway, full one hundred feet in width and almost as much in height.
Before this enormous cavern the millionaire brought the Seal to, with her brow pointing directly into the darkness, which even the rays of the searchlight failed to dispel for more than a few yards distant.
“I reckon we might do worse than try this,” he suggested.
“Take her in,” Mervyn said eagerly; “there is a chance. We can but return, should it prove to be a cul-de-sac.”
Forthwith the submarine passed cautiously through the archway into the great domed chamber which opened beyond.
Through this she crept, with searchlight flashing on the alabaster walls, till a second archway loomed before her, smaller than the first, yet wide enough to give her passage.