white patches, must be
open water. Furthermore, it was to leeward, and therefore to be reached
much more quickly and easily than the open water which we had left
behind us sometime during the night, and to return to which it would be
necessary for us to beat to windward through a more or less intricate
and difficult channel. It was undoubtedly true that somewhere out there
to windward there existed a channel carrying a sufficient depth of water
to float the ship, for she had already passed through it; but our
difficulty would be to pick that particular channel out from among the
many intersecting streaks of unbroken water that showed so elusively
among the breakers. And if it were possible to hit off that channel, or
indeed any channel leading without a break into clear water, was the
wind sufficiently free to enable us to lay our course along it without
breaking tacks? I doubted it very much; and if not, or if at a critical
moment the wind should shift a point or two, the ship must inevitably go
ashore and become a wreck; for I could nowhere see a channel wide enough
to allow the ship to work in. Arguing thus, I soon came to the
conclusion that I must look to leeward for the channel that must conduct
us to open water and safety.

I accordingly directed my gaze northward; and for some time my eyes
searched that vast expanse of seething whiteness for an unbroken channel
leading out into blue water from the lagoon-like sheet of water across
which the _Mercury_ was then ratching. But all in vain; for while there
were plenty of channels leading from the lagoon through the broken water
to leeward, not one of them seemed to be continuous all the way across
the reef and right out to blue water. They intersected, merged into,
and branched off from each other in the most bewildering fashion, and
there were at least half a dozen that seemed to lead into open water;
but I quite failed to trace a connection between them and those that led
out of the lagoon. At length, however, when the ship had reached the
easternmost extremity of the lagoon, and the moment had arrived when it
became necessary for us to go about and retrace our steps, we suddenly
opened out a small patch of unbroken water away to the north-eastward,
with a clear, well-defined channel leading from it to the open sea.
While I was still regarding this part of the reef I caught a momentary
glimpse of another channel leading into the small patch of unbroken
wat