THE PLANETARIUM, AND ASTRONOMICAL CALCULATOR, CONTAINING The Distances, Diameters, Periodical and Diurnal Revolutions of all the Planets in and the periods of their Revolutions around, their respective Primaries; " together with the method of calculating those Distances, Diameters and KF 2531 HARVAR Svatis Entered according to the Act of Congress, October, 1833, by In the Clerk's Office of the District Court of the Southern District of New York. PREFACE. IN presenting the following pages to the public, I will briefly remark, that the people generally are grossly ignorant in the important and engaging science of Astronomy. Scarcely one in a county is found capable of calculating with exactness and accuracy the time of an eclipse, or conjunction and opposition of the Sun and Moon. Is it for lack of abilities? No.-There are no people in the world who possess better natural faculties for acquiring knowledge of every description, than those who inhabit the United States of America. In this land of liberty, much has been done, and much still remains to be done, for the benefit of the rising generation. Schools, Academies, and Colleges have been erected, for the purpose of facilitating and extending information and instruction among the youth. Gentlemen possessing the most profound abilities and acquirements, have engaged in the truly laudable employment of disseminating a knowledge of the sciences, both of the useful and ornamental description. Still, this branch of the Mathematical science, called Astronomy, has been almost totally neglected, especially among the common people. From what source has this originated? I answer, from a scarcity of books, well calculated to give the necessary instruction. Though there be many productions possessing merit, which 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 possess 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. 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 endeavouring to meliorate the condition of man, by improving the mind and enlightening the understanding, will have the pleasing reflection, that he has removed some of the shackles of ignorance, and supplied a fund of useful and interesting knowledge. THE COMPILER |