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lated to give the necessary instruction. Though there are many productions possessing merit, and are of importance to the rising generation, yet they are deficient in the tables necessary for the calculation, and protraction of eclipses. The works of Ferguson, Enfield and others, from which this is principally compiled, contain all that is necessary; but the expense renders them beyond the means of many, who perhaps posses the best abilities in our land. Extensive volumes are not well calculated for the use of Schools; for a Student is under the necessity of reading so much unessential, and uninteresting matter, that the essence is lost, in the multiplicity of words; and for these reasons, many of the teachers have neglected this useful, and important branch of the Mathematical science. I have long impatiently beheld the evil, without an opportunity of providing a remedy, until the present period.

I now present to this enlightened community, a volume within the means of almost every person; containing all the essential parts of Astronomy, adapted to the use of Schools and Academies; made so plain and easy to be understood, that a lad of twelve years of age, whose knowledge of Arithmetic extends to the single rule of proportion, can, in the short space of one or two weeks, be taught to calculate an eclipse; and many possessing riper years, from the precepts and examples given in the work, will be found capable of accomplishing it, without the aid of any other teacher.

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The tables, (with the exception of two,) I have wholly calculated, and then duly compared them with those of Ferguson. Great care has also been taken, to present the work to the public, free from errors.

Should the following pages meet the approbation of a generous and enlightened community, and be the means of extending the knowledge of this important branch of Education; not only to the rising generation, but to those of maturer years, the Compiler, whose best abilities have hitherto been employed in endeavoring to meliorate the condition of man, by improving the mind and enlightening the understanding, will have the sublime satisfaction, of removing some of the shackles of ignorance, and building up a fund of useful and interesting knowledge upon its ruins.

THE COMPILER.

SECTION FIRST.

OF ASTRONOMY IN GENERAL.

Or all the sciences cultivated by mankind, Astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most interesting, and the most useful. By the knowledge derived from this science, not only the magnitude of the earth is discovered, the situation and extent of the Countries and Kingdoms 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

So that

superintendency of the Supreme Being. without any hyperbole, every man acquainted with this science, must exclaim with the immortal Dr. Young: "An undevout Astronomer is mad." From this branch of Mathematical knowledge, we also learn by what means, or laws, the Almighty Power and Wisdom of the Supreme Architect of the Uuiverse, are administered in continuing the wonderful harmony, order and connexion, observable throughout the planetary system; and are led by very powerful arguments, to form this pleasing and cheering sentiment, that minds capable of such deep researches, not only derive their origin from that Adorable Being, but are also incited to aspire after a more perfect knowledge of his nature, and a more strict conformity to his will.

By Astronomy we discover, that the earth is at so great a distance from the sun, that if seen from thence, it would appear no larger than a point; although its diameter is known to be nearly 8,000 miles: yet that distance is so small, compared with the earth's distance from 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 at least 190 millions of miles in diameter; for the earth in going round the sun, is 190 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 still remain the same; and a telescope which magnifies above 200 times, does not sensibly magnify them;