ggestions, had I only been keen-sighted enough to observe them and
smart enough to read their significance; but I believe the fact to be
that at that time I had no room in my mind for any other thought than
that of the navigation of the ship. It is true that for more than a
year it had been part of my daily duty, as a midshipman-apprentice
qualifying for the position of officer, to take observations of the
various heavenly bodies simultaneously with those of Captain Martin and
the mates, to work them out independently, and to submit my calculations
to the skipper--who examined and returned them with such written
comments as he deemed called for--with the result that I had long since
become proficient in the science of navigation. But this was a very
different thing. If on board the _Salamis_ I had chanced to make a
mistake, the worst that could have happened would have been a sharp
rebuke from the skipper for my carelessness, and an equally sharp
injunction to be more careful in future; whereas now, aboard the
_Mercury_, if I happened to make a miscalculation, there was nobody to
correct it; and although subsequent observations might reveal the error,
and no actual harm arise from its committal so long as the ship was in
mid-ocean, a comparatively trivial mistake committed when the ship
happened to be in the vicinity of rocks, or shoals, or approaching land,
might easily make all the difference between perfect safety and her
total loss, together with that of all hands. Hence, during those early
days, when the sense of grave responsibility lay heavy upon my young
shoulders, I could think of nothing but more or less abstruse
astronomical problems.

CHAPTER THREE.

AN UNPLEASANT SURPRISE.

The revelation came upon me, with the stunning effect of a thunder-clap,
on the day upon which we made the island of Saint Paul. The weather
during the whole of the preceding day had been brilliantly fine, with a
light air of wind that, breathing out from the south-east at daybreak,
had gradually hauled round until by noon it had settled at south; so
that when I took my meridian altitude of the sun for the determination
of our latitude, the _Mercury_ was heading straight for the spot where
my calculations declared the island to be, with all plain sail set to
her royals, and with the weather bracer slightly checked.

Upon working out my meridian altitude I found the ship's latitude to be
38 degrees 43 minutes south and we wer