tion of the earth.
The bright arc of the circle nearest the center is the path of the
North star. The other arcs are the impressions left by neighboring
stars, and it will be noticed that their brightness varies with
their relative brilliancy. Many are so faint as to be scarcely
distinguished, and, of course, telescopic power would reveal
myriads of heavenly bodies which leave no trace on a plate in an
ordinary camera. The North or pole star is commonly considered at
a point directly out from the axis of the earth, but the
photograph shows that it is not so located. The variation is known
astronomically to be 1-1/4 deg. There is a slight irregularity in
the position of the earth's axis, but the changes are so slow as
to be noticed only by the lapse of a thousand years. Five thousand
years ago the pole star was Draconis, and in eighteen thousand
years it will be Lyrae. We have direct evidence of the change of
the earth's axis in one of the Egyptian pyramids where an aperture
marked the position of the pole star in ancient times, and from
this it is now deviated considerable.
[Illustration: Photograph of the North Star]
This experiment is within the reach of everyone owning a camera.
The photograph shown was taken by an ordinary instrument, using a
standard plate of common speed. The largest stop was used and the
only requirement beyond this is to adjust the camera in a position
at the proper inclination and to make the exposure for as long as
desired. On long winter nights the exposure may be extended to 12
hours, in which event the curves would be lengthened to full
half-circles.
The North star is one of the easiest to locate in the entire
heavens. The constellation known as the Great Dipper is near by,
and the two stars that mark the corners of the dipper on the
extremity farthest from the handle lie in a line that passes
across the North star. These two stars in the Great Dipper are
called the pointers. The North Star is of considerable brilliancy,
though by no means the brightest in that part of the heavens.
--Contributed by O. S. B.
** How to Relight a Match [444]
A match may be a small thing on which to practice economy and yet
a great many times one wishes to relight a match either for
economy or necessity. The usual method is to place the burnt
portion of the match in the flame to be relighted as shown
[Illustration: Relighting a Match]
in Fig. 1. It is very hard to relight the charred end
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