ut of
sight of land, enabling long voyages to be safely made; the marvellous
improvements in ship-building, which shortened passages by sailing
vessels, and vastly reduced freights even before steam gave an
independent force to the carrier--each and all were done by small
advances, which together contributed to the general movement of
mankind.... Each owes all to the others. The forgotten inventors live
for ever in the usefulness of the work they have done and the progress
they have striven for."--H. M. Hyndman.

One of the most extraordinary things connected with Applied Science is
the method by which the Navigator is enabled to find the exact spot of
sea on which his ship rides. There may be nothing but water and sky
within his view; he may be in the midst of the ocean, or gradually
nearing the land; the curvature of the globe baffles the search of his
telescope; but if he have a correct chronometer, and can make an
astronomical observation, he may readily ascertain his longitude, and
know his approximate position--how far he is from home, as well as from
his intended destination. He is even enabled, at some special place,
to send down his grappling-irons into the sea, and pick up an
electrical cable for examination and repair.

This is the result of a knowledge of Practical Astronomy. "Place an
astronomer," says Mr. Newcomb, "on board a ship; blindfold him; carry
him by any route to any ocean on the globe, whether under the tropics
or in one of the frigid zones; land him on the wildest rock that can be
found; remove his bandage, and give him a chronometer regulated to
Greenwich or Washington time, a transit instrument with the proper
appliances, and the necessary books and tables, and in a single clear
night he can tell his position within a hundred yards by observations
of the stars. This, from a utilitarian point of view, is one of the
most important operations of Practical Astronomy."[2]

The Marine Chronometer was the outcome of the crying want of the
sixteenth century for an instrument that should assist the navigator to
find his longitude on the pathless ocean. Spain was then the principal
naval power; she was the most potent monarchy in Europe, and held half
America under her sway. Philip III. offered 100,000 crowns for any
discovery by means of which the longitude might be determined by a
better method than by the log, which was found very defective. Holland
next became a great naval power, and fol