ounded. The pathways of the ocean
are marked out in the sky above. The eternal lights of the heavens are
the only Pharos whose beams never fail, which no tempest can shake from
its foundation. Within my recollection, it was deemed a necessary
qualification for the master and the mate of a merchant-ship, and even
for a prime hand, to be able to "work a lunar," as it was called. The
improvements in the chronometer have in practice, to a great extent,
superseded this laborious operation; but observation remains, and
unquestionably will for ever remain, the only dependence for
ascertaining the ship's time and deducting the longitude from the
comparison of that time with the chronometer.

[Footnote A: Grant's _Physical Astronomy_, p. 460.]

It may, perhaps, be thought that astronomical science is brought already
to such a state of perfection that nothing more is to be desired, or at
least that nothing more is attainable, in reference to such practicable
applications as I have described. This, however, is an idea which
generous minds will reject, in this, as in every other department of
human knowledge. In astronomy, as in every thing else, the discoveries
already made, theoretical or practical, instead of exhausting the
science, or putting a limit to its advancement, do but furnish the means
and instruments of further progress. I have no doubt we live on the
verge of discoveries and inventions, in every department, as brilliant
as any that have ever been made; that there are new truths, new facts,
ready to start into recognition on every side; and it seems to me there
never was an age, since the dawn of time, when men ought to be less
disposed to rest satisfied with the progress already made, than the age
in which we live; for there never was an age more distinguished for
ingenious research, for novel result, and bold generalization.

That no further improvement is desirable in the means and methods of
ascertaining the ship's place at sea, no one I think will from
experience be disposed to assert. The last time I crossed the Atlantic,
I walked the quarter-deck with the officer in charge of the noble
vessel, on one occasion, when we were driving along before a leading
breeze and under a head of steam, beneath a starless sky at midnight, at
the rate certainly of ten or eleven miles an hour. There is something
sublime, but approaching the terrible, in such a scene;--the rayless
gloom, the midnight chill,--the awful swell of t