"We must have gone in pretty deep," commented Amos Henderson. "Luckily it was soft mud instead of a rocky reef or we'd have damaged the ship beyond repair."
For several minutes the engines were kept on the reverse, but all to no purpose. The sticky mud was like glue in its holding power and the ship had buried her prow deep into it.
"I guess we'll have to dig our way out," said the professor, after taking a careful view of the big mud bank from the conning tower. "Washington, get out the diving suits and the spades."
"Are we really going out in the water to dig?" asked Tom.
"Of course," said Mr. Henderson. "You'll be as safe as in the ship, wearing one of my diving suits. We'll all have to help, for it will be quite a task."
The queer suits were brought out, and the reservoirs in the helmets were filled with compressed air. It was decided to have Washington remain within the Porpoise, to watch the machinery and start the engine when the digging was partly done, in order to see if the ship would not pull herself free when some of the mud had been removed from the prow.
"And we may need Washington for another purpose," said the professor.
"What for?" asked Mark.
"Well, he'll have to stay by the diving tank, to let us in quickly in case of emergency."
"Do you think there'll be an emergency?" asked Jack.