"Any danger?" asked Ned.
"Not that I know of, only it may make it more difficult for us to see the wreck of the Pandora."
As Tom turned to leave the cabin the submarine suddenly ceased moving. And she came to a gradual stop as though she had been "snubbed" by a mooring line.
"I wonder what's the matter!" exclaimed Tom. "We can't have come upon the wreck so soon."
At that moment a man entered the cabin.
"Trouble, Mr. Swift!" he reported.
"What kind?" asked Tom.
"Our propellers are tangled with a mass of serpent weed," was the answer. "They're both fouled, and we can't budge."
"Bless my anchor chain!" ejaculated Mr. Damon. "Stuck again!"