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Newcomb, Simon, 1835-1909

"Side-Lights on Astronomy and Kindred Fields of Popular Science"


Jack is a superstitious fellow, and we may be sure that he was not
less so in former times than he is today. From his point of view
there was something uncanny in so very simple a contrivance as a
floating straw persistently showing him the direction in which he
must sail. It made him very uncomfortable to go to sea under the
guidance of an invisible power. But with him, as with the rest of
us, familiarity breeds contempt, and it did not take more than a
generation to show that much good and no harm came to those who
used the magic pointer.
The modern compass, as made in the most approved form for naval
and other large ships, is the liquid one. This does not mean that
the card bearing the needle floats on the liquid, but only that a
part of the force is taken off from the pivot on which it turns,
so as to make the friction as small as possible, and to prevent
the oscillation back and forth which would continually go on if
the card were perfectly free to turn. The compass-card is marked
not only with the thirty-two familiar points of the compass, but
is also divided into degrees. In the most accurate navigation it
is probable that very little use of the points is made, the ship
being directed according to the degrees.


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