planets Venus, Jupiter, Mars, Saturn, Mercury, and Uranus are given,
accompanied by those of two conspicuous stars. This information is very
valuable to the telescopist. In the first place, as we shall presently
see, it shows him what planets are well situated for observation, and
secondly it enables him to map down the path of any planet from day to
day among the fixed stars. This is a very useful exercise, by the way,
and also a very instructive one. The student may either make use of the
regular maps and mark down the planet's path in pencil, taking a light
curve through the points given by the data in his almanac, or he may lay
down a set of meridians suited to the part of the heavens traversed by
the planet, and then proceed to mark in the planet's path and the stars,
taking the latter either from his maps or from a convenient list of
stars.[9] My 'Handbook of the Stars' has been constructed to aid the
student in these processes. It must be noticed that old maps are not
suited for the work, because, through precession, the stars are all out
of place as respects R.A. and Dec. Even the Society's maps, constructed
so as to be right for 1830, are beginning to be out of date. But a
matter of 20 or 30 years either way is not important.[10] My Maps,
Handbook and Zodiac-chart have been constructed for the year 1880, so as
to be serviceable for the next fifty years or so.

Next, below the table of the planets, we have a set of vertical
columns. These are, in order, the days of the month, the calendar--in
which are included some astronomical notices, amongst others the
diameter of Saturn on different dates, the hours at which the sun rises
and sets, the sun's right ascension, declination, diameter, and
longitude; then eight columns which do not concern the observer; after
which come the hours at which the moon rises and sets, the moon's age;
and lastly (so far as the observer is concerned) an important column
about Jupiter's system of satellites.