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(c) The Points are the Poles of the Ecliptic, the Equinoxes, and the Solstices.
The Poles of the Ecliptic are the points where the axis of the earth's orbit meets the Celestial Sphere. (Little used.)
The Equinoxes are the points where the ecliptio intersects the equinoctial. The place where the sun crosses the equinoctial* in going North, which occurs about the 21st of March, is called the Vernal Equinox. The place where the sun crosses the equinoctial in going South, which occurs about the 21st of September, is called the Autumnal Equinox. The Solstices are the two points of the ecliptic most distant from the Equator; or they may be considered to mark the sun's furthest declination, North and South of the equinoctial. The Summer Solstice occurs about the 22d of June; the Winter Solstice occurs about the 22d of December.
(d) The Measurements are celestial longitude and latitude.
Celestial longitude is distance from the Vernal Equinox measured on the ecliptic, eastward.
Celestial latitude is distance from the ecliptic measured on a Subordinate circle, north or south.
A belt of the Celestial Sphere, 8° on each side of the ecliptic, is styled the Zodiac. This is of very
• "This is what is commonly called " crossing the line."
high antiquity, having been in use among the ancient Hindoos and Egyptians. The Zodiac is divided into twelve equal parts—of 30° each—called Signs, to each of which a fanciful name is given. The following are the names of the
Signs Of The Zodiac.
Cancer . ®
"The first, f, indicates the horns of the Earn; the second, », the head and horns of the Bull; the barb attached to a sort of letter tit, designates the Scorpion; the arrow, t, sufficiently points to Sagittarius; v5 is formed from the Greek letters rp, the two first letters of rpayos, a goat. Finally, a balance, the flowing of water, and two fishes, tied by a string, may be imagined in ^, a?, and a, the signs of Libra, Aquarius, and Pisces."
The Solar System is mainly comprised within the limits of the Zodiac. It consists of—
1. The Sun—the centre.
2. The major planets—Vulcan (undetermined), Mercury,
Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
8. The minor planets, at present one hundred and seventeen in number. (The paths of some extend a little outside the Zodiac.)
4 The satellites or moons, eighteen in number, which revolve around the different planets.
5. Meteors and shooting-stars.
6. Nine comets whose orbits have been computed, and
over two hundred of which little is known.
7. The Zodiacal Light.
HOW WE ABE TO IMAGINE THE SOLAR SYSTEM TO OUH
Selyes.—We are to think of it as suspended in space; being held up, not by any visible object, but in accordance with the law of Universal Gravitation discovered by Newton, whereby each planet attracts every other planet and is in turn attracted by alL First, the Sun, a great central globe, so vast as to overcome the attraction of all the planets, and compel them to circle around him; next, the planets, each turning on its axis while it flies around the