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BOOK vn.
THE STARRY HEAVENS.
CHAPTER I.
The Pole-Star — Not always the same. — Curious Circumstance con-nected with the Pyramids of Egypt. — Stars classified into differentMagnitudes. — Antiquity of the Custom of forming them into Groups.— Anomalies of the present System. —Stellar Photometry. — Dis-tances of the Stars . — How distinguished. — Antiquity of the Customof naming Stars. — Invention of the Zodiac. — Letters introduced byBayer. — Effects of the increased Care bestowed on Observations of theStars . — Ideas of the Ancients on the Stars . — Remarks by Sir J.Herschel.
If, on some clear evening, the reader will take the trouble tostation himself on the summit of any rising ground, and casthis eye upwards, he will see the sky spangled with countlessmultitudes of brilliant specks of light; these are the fixed stars(we shall presently see that this appellation is not strictly cor-rect) ; an attentive observer will soon notice, also, that the starshe is contemplating seem to revolve in a body around one oftheir number situated in the north, about midway between thehorizon and the zenith ; this is the Pole-star, so called fromits being near the*pole of the celestial equator. On account,however, of the precession of the equinoxes, the present Pole-star (a Ursse Minoris) will not always be so ; the true pole is
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