The Intermountain Catholic. (Salt Lake City [Utah] ;) 1899-1920, 1909-10-30
THE SEXTANT AND THE NORTH POLE.
Salt Lake City, Utah, Oct, 16, 1869.

Salt Lake City, Utah, Oct 16, 1909
Editor Intermountain Catholic, City
Sr:-In common with many others, [ very
much interested in the accounts of the discovery of
the north pole by Cook and Peary. Would You
kindly tell me something about the sextant, the use
of it, and the meaning of Pearys note about wait
ing for the to appear that he could take his
observations MARY HAROLD.
A studious young lady interested in the north
pole controversy wants to know something about
'the of the sextant, and the meaning of Pearys
note about waiting for the to appear so that he
could take his observations"
Everybody who has crossed the ocean, or has
been long voyage out of sight of land, has
heard of the sextant if he has not seen it for it is
by the sextant that the ships position is ascertained
and, in sense, the ships course determined The
sextant is instrument used to measure the att
tude of heavenly body above the horizon. or the
distance between objects The distribution, names
and of the several parts are too technical for
the understanding of the average reader, and can
not be comprehensvely explained without illustra-
TONS
This instrument enables the officers to deter
mine within few miles the exact place of the ship
upon the ocean. The sextant, then, is an instru-
ment for measuring angles between distant objects
It's name is derived from the latin sextans mean
ing the sixth of a circle Lecky in his wrinkles
in Practical Navigation" gives the history of the
sextant and describes its and its parts infinitely
The business of the sextant scientifically ex-
pressed by Lucien Smith in late edition of his
elements of Navigation" is to solve the astronom
zeal triangle. What the sailor and the explorer
wish to find out is the altitude height-of the
sun. AT sea, the actual horizon may appear where
water and sky seem to meet; but on land or ON q
solid body like ice it is necessary to use what is
called an artificial horizon" Usually this con-
sists of cast iron trough containing pure mercury
covered with glass roof to protect it from the
wind. A chronometer-a watch made to resist
changes in temperatures also necessary for if
the SUMS position altitude be taken at noon, an
error in determining longitude is of small import
ance. About the chronometer. The chronometer is
superior kind of a watch, so constructed that its
daily gain or loss by variation of temperature is re-
duced to a minimum. The machinery is of such
delicate construction that the greatest possible care
must be taken of it. It is never removed from its
place board, but kept as near the same tempera-
ture possible, and is protected by case lined
with soft wool, and hung on girnbals Ca combina-
ton of rings) It is wound up every day at pre-
cisely the same hour and the key turned slowly and
steadily
The altitude of the sun being taken, the declina-
ton position of the sun can then be found
worked out in the Nautical Almanac, without
which captain of ship would go to sea- These
two factors being found the almanac will tell him
where he is that is, his latitude.
1t was by this method and process that Cook and
Peary knew where they were night and day When
their sextant showed them the zenith--the point
straight over their heads-and the north star near
the same position, they would know they stood di-
rectly over the pole
Three possible errors only could occur One