With the aid of the charts, familiarize yourself with the appearance of the constellations by noticing the characteristic arrangements of their chief stars.

You need pay no attention to any except the bright stars, and those that are conspicuous enough to thrust themselves upon your attention.
Learn by observation at what seasons particular constellations are on, or near, the meridian--i.e., the north and south line through the middle of the heavens.

Make yourself especially familiar with the so-called zodiacal constellations, which are, in their order, running around the heavens from west to east: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricornus, Aquarius, and Pisces.

The importance of these particular constellations arises from the fact that it is across them that the tracks of the planets lie, and when you are familiar with the fixed stars belonging to them you will be able immediately to recognize a stranger appearing among them, and will correctly conclude that it is one of the planets.[21] How to tell which planet it may be, it is the object of this chapter to show you.

As an indispensable aid--unless you happen already to possess a complete star atlas on a larger scale--I have drawn the six charts of the zodiacal constellations and their neighbors that are included in this chapter.
[Footnote 21: In our latitudes, planets are never seen in the northern quarter of the sky.