The Expanse of Heaven - A Series of Essays on the Wonders of the Firmament (Classic Reprint)

The object which the Author and Publisher of this little work have proposed to themselves, has been the production, at a moderate price, of a useful and reliable guide to the amateur telescopist.

Among the celestial phenomena described or figured in this treatise, by far the larger number may be profitably examined with small telescopes, and there are none which are beyond the range of a good 3-inch achromatic.

The work also treats of the construction of telescopes, the nature and use of starmaps, and other subjects connected with the requirements of amateur observers.

Half hours with the Telescope

To the student of science, accustomed to recognise the operation of law in all phenomena, even though the nature of the law and the manner of its operation may be unknown, there is something strange in the prevalent belief in luck. In the operations of nature and in the actions of men, in commercial transactions and in chance games, the great majority of men recognise the prevalence of something outside law-the good fortune or the bad fortune of men or of nations, the luckiness or unluckiness of special times and seasons-in fine (though they would hardly admit as much in words), the influence of something extranatural if not supernatural.

This is true alike of great things and of small; of matters having a certain dignity, real or apparent, and of matters which seem utterly contemptible. Napoleon announcing that a certain star (as he supposed) seen in full daylight was his star and indicated at the moment the ascendency of his fortune, or William the Conqueror proclaiming, as he rose with hands full of earth from his accidental fall on the Sussex shore, that he was destined by fate to seize England, may not seem comparable with a gambler who says that he shall win because he is in the vein, or with a player at whist who rejoices that the cards he and his partner use are of a particular colour, or expects a change from bad

to good luck because he has turned his chair round thrice; but one and all are alike absurd in the eyes of the student of science, who sees law, and not luck, in all things that happen.

The laws of luck

It is very easy to gain a knowledge of the stars, if the learner sets to work in the proper manner. But he commonly meets with a difficulty at the outset of his task. He provides himself with a set of the ordinary star maps, and then finds himself at a loss how to make use of them. Such maps tell him nothing of the position of the constellations on the sky. If he happen to recognize a constellation, then indeed his maps, if properly constructed, will tell him the names of the stars forming the constellation, and also he may be able to recognize a few of the neighboring constellations. But when he has done this he may meet with a new difficulty, even as respects this very constellation. For if he look for it again some months later, he will neither find it in its former place nor will it present the same aspect, -if indeed it happen to be above the horizon at all.

It is clear, then, that what the learner wants is a set of maps specially constructed to show him in what part of the sky the constellations are to be looked for. He ought on any night of the year to be able to turn at once to the proper map, and in that map he ought to see at once what to look for, toward what point of the compass each visible constellation lies, and how high it is above the horizon. And, if possible (as the present work shows is the case), one map ought to suffice to exhibit the aspect of the whole heavens, in order that the beginner may not be confused by turning from map to map, and trying to find out how each fits in with the others.

The Expanse of Heaven - A Series of Essays on the Wonders of the Firmament (Classic Reprint)

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