"Empty the reserve tanks," ordered Captain Restronguet, for the "Aphrodite" was now drawing ten feet for'ard and twelve aft. Quickly the foremost tank was emptied, but the after one, in spite of the action of the powerful pumps, refused to be discharged. Consequently the draught for'ard decreased while the submarine's stern sank lower into the slimy mud.
"Full speed astern," was the next order, but beyond churning up the brownish black ooze the propellers failed to do the slightest good.
"Lay out an anchor, Mr. Devoran," exclaimed his superior officer. "Be sharp, for the tide is falling."
Hastily the boat was lowered, the heaviest anchor slung underneath, and laid out a hundred yards astern. The stout hempen hawser was led to the motor capstan, but as the powerful machinery made it revolve it simply "walked home" with the anchor. The soft mud offered little or no resistance to its broad palm.
The "Aphrodite" seemed doomed to remain hard and fast for another ten hours. Night with all its terrors would envelop her ere the next tide was at its height, and to work in the germ-laden mists was to court the deadly fever.
"Can the ballast tank be got at from the inside, sir?" asked Hythe, struck by an inspiration.
"Not without flooding one of the sub-divisions of Number Three Platform," replied Captain Restronguet. "But why do you ask?"
"I thought perhaps I might put on a diving-dress, and enter the tank and examine the valves."
"It's feasible," observed Captain Restronguet. "If you attempt it and succeed I shall be still more indebted to you."
"Then I have your permission?"