E-text prepared by Colin Bell, Brenda Lewis, David King, and the Online Distributed Proofreading Team (http://www.pgdp.net) from page images generously made available by Internet Archive (https://archive.org) Note: Project Gutenberg also has an HTML version of this file which includes the 466 original illustrations. See 58810-h.htm or 58810-h.zip: (https://www.gutenberg.org/cache/epub/58810/pg58810-images.html) or (https://www.gutenberg.org/files/58810/58810-h.zip) Images of the original pages are available through Internet Archive. See https://archive.org/details/heavensabovepopu00gillrich Transcriber's note: Text enclosed by underscores is in italics (_italics_). Superscripts, such as P to the second power, are shown by the caret character "^" before the superscript, such as P^2. Subscripts are similarly shown by an underscore before the subscript which is wrapped in curly braces, such as M_{2}. [Illustration: SPECTRA OF VARIOUS SOURCES OF LIGHT.] The Heavens Above: A Popular Handbook of Astronomy THE HEAVENS ABOVE: A Popular Handbook of Astronomy. by J. A. GILLET, Professor of Physics in the Normal College of the City of New York, and W. J. ROLFE, Formerly Head Master of the High School, Cambridge, Mass. With Six Lithographic Plates and Four Hundred and Sixty Wood Engravings. Potter, Ainsworth, & Co., New York and Chicago. 1882. Copyright by J. A. Gillet and W. J. Rolfe, 1882. Franklin Press: Rand, Avery, and Company, Boston. PREFACE. It has been the aim of the authors to give in this little book a brief, simple, and accurate account of the heavens as they are known to astronomers of the present day. It is believed that there is nothing in the book beyond the comprehension of readers of ordinary intelligence, and that it contains all the information on the subject of astronomy that is needful to a person of ordinary culture. The authors have carefully avoided dry and abstruse mathematical calculations, yet they have sought to make clear the methods by which astronomers have gained their knowledge of the heavens. The various kinds of telescopes and spectroscopes have been described, and their use in the study of the heavens has been fully explained.