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their flocks, their most valued possession. Then followed in order Taurus (the bull) and Gemini (the twins), called from the herds, which were esteemed next in value. At the summer solstice the sun appears to stop, and, crab-like, to crawl backward; hence the name Cancer (the crab). "When the sun is in Leo, the brooks being dry, the lion leaves his lurking-place and becomes a terror to all. Virgo comes next, when the virgins glean in the summer harvest. At the autumnal equinox the days and nights are equally balanced, and this is beautifully represented by Libra (the scales). The vegetation decays in the fall, causing sickness and death; the Scorpion, that stings as it recedes, is suggestive of this Parthian warfare. Sagittarius (the archer) tells of the hunting month. Capricornus (the goat), which delights in climbing lofty precipices, denotes how at the winter solstice the sun begins to climb the sky on his return north. Aquarius (the waterbearer) is a natural emblem of the rainy season. Pisces (the fishes) is the month for fishing.
Signs And Constellations Do Not Agree.—By the precession of the equinoxes, as we have before described on page 121, the signs have fallen back along the ecliptic about 30°, so that those stars which were, in the infancy of astronomy, in the sign Aries (V) are now in Taurus (b), and those which were in the sign Pisces (M) are now in Aries (T).*
* If the teacher put a pin at the centre of Fig. 72, and, drawing a sharp knife between the signs and the constellations, cause the inner part to revolve, the signs may Be turned before any constellation, and thus this change be clearly apprehended.
The accompanying cut may illustrate this more clearly.
SIGNS AND CONSTELLATIONS, AS THET NOW COMPARE IN THE
Permanence Of The Constellations.—The figures which the stars form, and the general appearance of the constellations, are due to the position we occupy. Could we cross the gulf of space beyond Neptune, the stars now so familiar to us would look strangely enough in their new groupings. As one in riding through a forest sees the trees apparently increase in size and open up to view before him, while they decrease in size and close in behind him, forming clusters and groups which constantly change as he passes along; so, as our earth travels with the solar system on its immense sidereal journey, the stars will grow larger and brighter in front, while those behind us will appear smaller and dimmer. Since, in addition to this,' the stars themselves are in motion with varying velocity and in different directions, the constellations must change still more rapidly, so as ultimately to transform entirely the appearance of the heavens. In time, the "bands of Orion" will be loosened, and the "Seven Sisters" will glide apart into remote space. Such are the diatances however, that, although these movements have been going on constantly, yet since the creation of man no variation has occurred that is perceptible, save to the watchful astronomer. Nothing in nature is as invariable as the stars. They are the standards of time. Myriads of years must elapse before new starmaps will be required. We need not, then, allow any fear of confusion to disturb us while we study the sky as it is.
Value Of The Stars In Practical Lipe. — "The stars are the landmarks of the universe." They seem to be placed in the heavens by the Creator, not alone to elevate our thoughts and expand our conceptions of the infinite and eternal, but to afford us, amid the constant fluctuations of our own earth, something unchangeable and abiding. Every landmark about us is constantly changing, but over all shine the "eternal stars," each with its place so accurately marked, that to the astronomer and geographer no deception is possible. To the mariner, the heavens become a dial-plate, the figures on its face set with glittering stars, along which the moon travels as a shining hand that marks off the hours with an accuracy no clock can ever rival. Standing on the deck of his vessel, far out at sea, a single observation of the sun or stars decides his location in the waste of waters as accurately as if he were at home, and had caught sight of some old landmark he had known from his boyhood. In all the intricacies of surveying, the stars furnish the only immutable guide. Our clocks vainly strive to keep time with the celestial host. Thus, by a wise provision of Providence, even in the most common affairs of life, are we compelled to look for guidance from the shifting objects of earth up to the heavens above.
The Views Of The Ancients.—Standing in the light of our present knowledge, the ideas of the ancients seem almost incredible, and we can hardly understand how they could have been seriously entertained. Anaximenes (550 B. C.) thought that the stars were for ornament, and were nailed like bright studs into the crystalline sphere. Anaxagoras (450 B. c) considered that they were stones whirled up from the earth by the rapid motion of the ether around us, and that its inflammable properties set them on fire and caused them to shine as stars. Many schools of the Grecian philosophers—the Stoics, Epicureans, etc.—believed that they were celestial fires kept alive by matter that constantly streamed up to them from the centre of the heavens. The stars were at one time said to feed on air; at another, to be the breathing holes of the universe.
Three Zones Of Stars.—If we recall what was said on page 104, concerning the paths of the stars and appearance of the heavens at different seasons of the year, we shall see that the constellations are naturally divided into three zones. The first embraces those which are visible through the entire year; the second, those whose orbits can be seen only in part on any given night; and the third, those whose paths just graze our southern horizon, or never pass above it.
Northern Circumpolar Constellations.—These constellations in our latitude are visible every night. They may be easily traced by holding the book up toward the northern sky in such a way that Polaris and the Dipper on the map and in the heavens agree in position, and then locating the other constellations by comparison. As they revolve about Polaris, their places will vary with every successive night through the year. The cut represents them as they are seen at midnight of the winter solstice. At 6 P. M. of that day the right-hand side of the map should be held downward, and the