CI.5UA. Bk yiiXSb-H TRINITY COLLEGE LIBRARY DURHAM, NORTH CAROLINA Rec’d .H.QV LI A)9Q2 ML MAP OF THE MOON. SOUTH POLE s Digitized by the Internet Archive in 2016 with funding from Duke University Libraries https://archive.org/details/hourswiththreein01 nobl HOURS WITH A 3-INCH TELESCOPE PRINTED BY 5P0TTISW00DE AND CO., NEW -STREET SQUARE LONDON \*\ VWO HOURS WITH A THREE- INCH TELESCOPE BY CAPT. WM. NOBLE, F.R.A.S, F.R.M.S. HONORARY ASSOCIATE OF THE LIVERPOOL ASTRONOMICAL SOCIETY ETC. n / go INDUSTRIAL PUBLICATION COMPANY 15 DEY STREET NEW YORK 1886 i’g a. a H 7 5 3 H PREFACE. The following pages are, to a large extent, a reprint of a series of papers which, at the request of my friend Mr. Proctor, I wrote for the columns of ‘ Knowledge,’ in which they originally appeared. The work in its collected form simply aims at being a primer of the Three-inch Telescope, and is designed to instruct the very beginner in the use of an instrument of that size, mounted on a common table stand and unprovided wuth any means of finding objects in the sky by means of their co-ordinates. The reader is further supposed to know no more of the constellations than may be learned from ‘The Stars in their Seasons,’ w r hich forms one of the series of the ‘ Knowledge Library.’ In one sense, every single line in the book is original ; inas- much as every object referred to was actually described and drawn by myself, at the eye end of a telescope of three inches aperture. One thing I must most earnestly disclaim, and that is anything in the shape of competition or rivalry with any existing work treating of telescopic observation. My highest aspiration will be fulfilled if this little book should serve as an introduction to, and induce the amateur VI PREFACE. diligently to study, a work the charm of whose style is only equalled by the scientific value of its contents : I mean, of course, the ‘ Celestial Objects for Common Telescopes ’ of the late lamented Prebendary Webb. I should be proud indeed to feel that my unpretending rudimentary lessons had been the means of introducing the student to that treasure-house of the glories and beauties of the heavens, and should appreciate such a result as the highest reward that I could receive for the pains and trouble I have taken. CONTENTS CHAPTER PAGE I. THE INSTRUMENT I II. THE SUN . 8 III. THE MOON 14 IV. OCCULTATIONS OF STARS AND PLANETS BY THE MOON 44 V. MERCURY 50 VI. VENUS 53 VII. MARS 59 VIII. JUPITER 65 IX. SATURN 74 X. URANUS AND NEPTUNE 79 XI. DRAWING THE PLANETS 8l XII. THE FIXED STARS AND NEBULAE 86 MAP OF THE MOON Frontispiece HOURS WITH A THREE-INCH TELESCOPE. CHAPTER I. THE INSTRUMENT. This little book is written to furnish the very beginner in observational astronomy with such directions as shall enable him to employ, to the greatest possible advantage, the kind of instrument with which he will, in all probability, at first pro- vide himself. For, be it noted in the outset, it is not intended for the possessors of telescopes of considerable aperture equatorially mounted or furnished with elaborate rackwork movements in altitude and azimuth . 1 For the owners of such an abundant literature is already in existence ; and they have, at present, such admirable works as Webb’s ‘ Celestial Objects for Common Telescopes,’ Crossley, Gled- hill, and Wilson’s ‘ Handbook of Double Stars,’ Chambers’s one-volume edition of Smyth’s ‘ Celestial Cycle,’