Of course it might have been some promontory of the rocks under
the sea against which their telltale lead had struck; but there
was an instrument on board for taking soundings by means of a
lead suspended outside and a wire running through a water-proof
hole in the bottom of the vessel, and when the Dipsey had risen a
few fathoms, and was progressing very slowly, this instrument was
used at frequent intervals, and it was found that the electric
lead had not touched a rock projecting upward, and that the
bottom was almost level.

Mr. Gibbs's instrument gave him an approximate idea of the
vessel's depth in the water, and the dial connected with the
sounding apparatus told him hour by hour that the distance from
the bottom, as the vessel kept forward on the same plane, was
becoming less and less. Consequently he determined, so long as
he was able to proceed, to keep the Dipsey as near as possible at
a median distance between the ice and the bottom.

This was an anxious time. So long as they had felt that they had
plenty of sea-room the little party of adventurers had not yet
recognized any danger which they thought sufficient to deter them
from farther progress; but if the ice and the bottom were coming
together, what could they do? It was possible, by means of
explosives they carried, to shatter the ice above them; but
action of this kind had not been contemplated unless they should
find themselves at the pole and still shut in by ice. They did
not wish to get out into the open air at the point where they
found themselves; and, moreover, it would not have been safe to
explode their great bombs in such shallow water. A consultation
was held, and it was agreed that the best thing to do was to