But the limitations of a diving bell are so well recognized that
several inventors have tried adjusting movable arms to the bell,
to be operated by the man inside."

"Did they work?" asked Ned.

"After a fashion, yes. But I never heard of any case where the
gold and silver recovered paid for the expenses of making the
bell and sending men down in it. For it takes the same sort of
outfit to aid the man in the diving bell as it does the diver in
his usual rubber or steel suit. Air has to be pumped to him, and
he has to be lowered and raised."

"Well, isn't there any way of getting at this gold on the floor
of the ocean?" asked Ned, his enthusiasm a little cooled by the
practical "cold water" Tom had thrown.

"Oh, yes, of course there is, in a way," was the answer of the
young inventor. "Don't you remember how my father and I, with Mr.
Damon and Captain Weston, went in our submarine, the Advance, and
discovered the wreck of the Boldero?"

"I do recall that," admitted Ned.

"Well," resumed Tom, "there was a case of showing how much
trouble we had. An ordinary diving outfit never would have
answered. We had to locate the wreck, and a hard time we had
doing it. Then, when we found it, we had to ram the old ship and
blow it apart before we could get inside. Even after that we just
happened to discover the gold, as it were. I'm only mentioning