FOR THE LIBRARY, THE SCHOOL, AND THE OBSERVATORY. IN TWELVE CIRCULAR (WITH TWO INDEX PLATES). MAPS INTENDED AS A COMPANION TO 'WEBB'S CELESTIAL OBJECTS FOR COMMON TELESCOPES.' WITH A LETTERPRESS INTRODUCTION ON THE STUDY OF THE STARS, ILLUSTRATED BY SEVERAL WOODCUTS. BY RICHARD A. PROCTOR, B.A. CAMB. HON. SEC. R.A.S. AUTHOR OF THE SUN,' 'OTHER WORLDS THAN OURS,' 'SATURN AND ITS SYSTEM,' THE HANDBOOK OF THE STARS,' ETC. 'Why did not somebody teach me the Constellations, and make CARLYLE. SECOND EDITION. LONDON: LONGMANS, GREEN, AND CO. 1872. All rights reserved. PREFACE. THIS ATLAS is reduced from my large Star Atlas. The plan on which it has been constructed-briefly described in the accompanying letterpress-needs no special discussion here; because I have already fully dealt with it in the introduction to the large Atlas. I may remark, however, that the present work affords new and striking evidence of the advantages of the plan; for we have here a little book which can be carried in the pocket, while the small Atlas published by the Society for Diffusing Useful Knowledge is printed on sheets about sixteen inches. square; and yet the scale of the accompanying maps is larger than that of the S.D.U.K. Atlas. The reduction in size is gained chiefly by a reduction in the distortion of the maps, the maximum expansion due to this cause being fifty-eight times greater in the S.D.U.K. maps than in the present (see note at pp. 11, 12). Moreover, the twelve maps of this Atlas overlap, a fifth part of the heavens being included in the overlaps; so that each of the twelve maps exhibits a tenth part of the heavens. |