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  The improvements in the chronometer have in practice, to a great extent, superseded this laborious operation; but observation remains, and unquestionably will for ever remain, the only dependence for ascertaining the ship’s time and deducting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 the deep,—­the dismal moan of the wind through the rigging, the all but volcanic fires within the hold of the ship.  I scarce know an occasion in ordinary life in which a reflecting mind feels more keenly its hopeless dependence on irrational forces beyond its own control.  I asked my companion how nearly he could determine his ship’s place at sea under favorable circumstances.  Theoretically, he answered, I think, within a mile;—­practically and usually within three or four.  My next question was, how near do you think we may be to Cape Race;—­that dangerous headland which pushes its iron-bound unlighted bastions from the shore of Newfoundland far into the