"Impossible!" replied the engineer. "The valves are tightly closed; our furnaces are full up to the mouths."
"What difference! Fill them with cotton soaked in spirits; we must pass that frigate at any price."
At these words the most daring of the sailors looked at each other, but did not hesitate. Some bales of cotton were thrown into the engine-room, a barrel of spirits broached over them, and this expensive fuel placed, not without danger, in the red-hot furnaces. The stokers could no longer hear each other speak for the roaring of the flames. Soon the metal plates of the furnaces became red-hot; the pistons worked like the pistons of a locomotive; the steamgauge showed a frightful tension; the steamer flew over the water; her boards creaked, and her chimneys threw out volumes of smoke mingled with flames. She was going at a headlong speed, but, nevertheless, she was gaining on the frigate-passed her, distanced her, and in ten minutes was out of the channel.
"Saved!" cried the Captain.
"Saved!" echoed the crew, clapping their hands.
Already the Charleston beacon was disappearing in the south-west; the sound of firing from the batteries grew fainter, and it might with reason be thought that the danger was all past, when a shell from a gun-boat cruising at large was hurled whizzing through the air. It was easy to trace its course, thanks to the line of fire which followed it.
Then was a moment of anxiety impossible to describe; every one was silent, and each watched fearfully the arch described by the projectile. Nothing could be done to escape it, and in a few seconds it fell with a frightful noise on the fore-deck of the Dolphin.
The terrified sailors crowded to the stern, and no one dared move a step, whilst the shell was burning with a brisk crackle.
But one brave man alone among them ran up to the formidable weapon of destruction. It was Crockston; he took the shell in his strong arms, whilst showers of sparks were falling from it; then, with a superhuman effort, he threw it overboard.
Hardly had the shell reached the surface of the water when it burst with a frightful report.