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tronomy, Chronology, and the astronomical
Moons to each other, and to the Diameter of
Page CHAP. XVIII. Of Eclipses: Their Number and Periods. A large
Catalogue of Ancient and Modern Eclipses, 263
Astronomical Tables are constructed, and the
320 XX. Of the fixed Stars,
370 XXI. Of the Division of Time. A perpetual Table of
New Moons. The Times of the Birth and Death
391 XXII. A Description of the astronomical Machinery,
serving to explain and illustrate the foregoing
432 XXIII. The Method of finding the Distances of the Planeis from the Sun,
465 Art. I. Concerning Parallaxes, and their Use in general, 467 Art. II. Shewing how to find the horizontal Parallax of
Venus by Observation, and from thence, by
472 ABt. III. Containing Doctor Halley's Dissertation on
the Method of finding the Sun's Parallax and
482 ART. IV. Shewing that the whole Method proposed by the
Doctor cannot be put in Practice, and why, 498 Art. V. Shewing how to project the Transit of Venus on
the Sun's Disc, as seen from different Places of
500 ART. VI. Concerning the Map of the Transit,
520 Art. VII. Containing an Account of Mr. Horrox's Observa
tion of the Transit of Venus over the Sun, in
521 Art. VIII. Containing a short Account of some Observations
of the Transit of Venus, A. D. 1761, June 6th;
Of Astronomy in general.
1. O "
F all the sciences cultivated by mankind, The gener
astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most inter- my. esting, and the most useful. For, by knowledge derived from this science, not only the magnitude of the earth is discovered, the situation and extent of the countries and kingdoms upon it ascertained, trade and commerce carried on to the remotest parts of the world, and the various products of several countries distributed for the health, comfort, and conveniency of its inhabitants; but our very faculties are enlarged with the grandeur of the ideas it conveys, our minds exalted above the low contracted prejudices of the vulgar, and our understandings clearly convinced, and affected with the conviction, of the existence, wisdom, power, goodness, immutability, and superintendency of the SUPREME BEING. So that, without an hyperbole,
« An undevout astronomer is mad.*"}
2. From this branch of knowledge we also learn by what means or laws the Almighty carries on, and continues, the wonderful harmony, order, and connexion, observable throughout the planetary system; and are led, by very powerful arguments, to form this pleasing deduction—that minds capable
Dr. Young's Night Thoughts,
of such deep researches, not only derive their ori. gin from that adorable Being, but are also incited to aspire after a more perfect knowledge of his na
ture, and a stricter conformity to his will. The Earth 3. By astronomy, we discover that the Earth is but a point
at so great a distance from the Sun, that it seen from from the thence it would appear no larger than a point ; alSun. though its circumference is known to be 25,020
miles. Yet even this distance is so small, compared with that of the fixed stars, that if the orbit in which the Earth moves round the Sun were solid, and seen from the nearest star, it would likewise appear no larger than a point; although it is about 162 mil. hons of miles in diameter. For the Earth, in going round the Sun, is 162 millions of miles nearer to some of the stars at one time of the year, than at another; and yet their apparent magnitudes, situations and distances from one another, still remain the same; and a telescope which magnifies above 200 times, does not sensibly magnify them. This proves them to be at least 400 thousand times farther from us than we are from the Sun.
4. It is not to be imagined that all the stars are placed in one concave surface, so as to be equally distant from us; but that they are placed at im. mense distances from one another, through unli. mited space. So that there may be as great a distance between any two neighbouring stars, as between the Sun and those which are nearest to him.
An observer, therefore, who is nearest any fixed The stars star, will look upon it alone as a real Sun; and conare suns, sider the rest as so many shining points, placed at
equal distances from him in the firmament.
5. By the help of telescopes we discover thousands of stars which are invisible to the bare eye; and
the better our glasses are, still the more stars become and innu. visible: so that we can set no limits either to their
number or their distances. The celebrated HUY. GENS carried his thoughts so far, as to believe it not impossible that there may be stars at such
inconceivable distances, that their light has not yet reached the Earth since its creation ; although the velocity of light be a million of times greater than the velocity of a cannon-ball, as shall be demonstrated afterward, ý 197. 216.--And, as Mr. AdDISON very justly observes, this thought is far from being extravagant, when we consider that the universe is the work of infinite power, prompted by infinite goodness; having an infinite space to exert itself in; so that our imaginations can set no bounds to it.
6t The Sun appears very bright and large in Why the comparison with the fixed stars, because we keep constantly near the Sun, in comparison with our ger than immense distance from the stars. For, a spectator placed as near to any star as we are to the Sun, would see that star a body as large and bright as the Sun appears to us : and a spectator as far distant from the sun as we are from the stars, would see the Sun as small as we see a star, divested of all its circumvolving planets; and would reckon it one of the stars in numbering them.
7. The stars, being at such immense distances The star's from the Sun, cannot possibly receive from him so are not en., strong a light as they seem to have ; nor any bright- by the ness sufficient to make them visible to us. For the Sun. Sun's rays must be so scattered and dissipated before they reach such remote objects, that they can never be transmitted back to our eyes, so as to render these objects visible by reflection. The stars therefore shine with their own native and unborrowed lustre, as the Sun does. And since each par. ticular star, as well as the Sun, is confined to a particular portion of space, it is plain that the stars are of the same nature with the Sun.
8. It is no ways probable that the Almighty, who always acts with infinite wisdom, and does nothing in vain, should create so many glorious suns, fit for so many important purposes, and place them at such distances from one another, without pro