is charted all right, but there is no name given to it. The
captain says it is a sort of lost island, and they never thought enough of
it to give it a name or if it had one they didn't think it was good enough
to put on the chart."

"Lost Island is a good enough name for us," observed Jack. "Suppose we
call it that while we are here. That will not be long, I suppose."

"H'm! I don't know about that," Billy returned. "They have the yacht
afloat all right. They started the engines, and backed her off a sand bank
or whatever it was we were on, and are now in fairly deep water, but as to
leaving the island that is another matter."

"How is it?" asked all the boys in a breath.

"Because there is a line of reefs stretching right across the mouth of the
bay, and there seems to be no way of getting beyond them. There seem to be
openings here and there, but they are so narrow that the captain does not
think it wise to try to go through them."

"Then we are lost on Lost Island, and are lost ourselves," said Jack.

CHAPTER V

EXPLORING THE ISLAND

The boys returned to the yacht in time for dinner, and here their
situation was talked over by the doctor and the captain, the former
assuring the boys that there was no great danger, for the yacht was
equipped with a wireless service, and the captain could easily make his
predicament known, and vessels would doubtless be sent to his relief.

"We may pursue our studies as usual," the doctor continued, whereupon
there were wry looks upon the faces of many of the boys, "and as soon as
we get away from here we will pursue our voyage. It is simply an incident,
not an accident in our plans as arranged."

After dinner Jack got one of the yacht's boats, and took Dick and young
Smith with him to the mouth of the bay to get a view of the reefs.

For some little distance they could not see the opening of the bay on
account of its windings, the hills preventing them from getting a view of
the sea, but at length in rounding a wooded point they came in sight of
it.

There were reefs in front of them, at some little distance, and points of
rocks on both sides, the outer bay being of considerable size, but
generally exposed to the weather, which they were not in the inner bay.

They pushed on for some little distance, but not too near the reefs, where
they would be exposed to the force of the surf that dashed over the latter
and Jack presently pointed out a strange looking object