Excerpt from Star Atlas Containing Stars Visible to the Naked Eye and Clusters, Nebulae and Double Stars Visible in Small Telescopes, Together With Variable Stars, Red Stars, Characteristic Star Groups, Ancient Constellation Figures and an Explanatory Text

The maps are, on a large scale and are few in number, with liberal overlaps. Con forming with the plan of systematic study outlined in the text there are six maps, two circumpolar, and four whose areas cover the region between declination N. 40° and S. 40° They are subdivided into four divisions corresponding with the four divisions into which the sky is divided by the equinoctial and solstitial colures. The projection is stereographic, chosen chiefly because of the gradual narrowing of the hour circles on the equatorial maps as the declination increases, and the better correspondence of the equatorial and polar maps at their marginal overlaps. The' six skeleton maps are reduced from the larger ones, and are designed to give the characteristic stellar figures of each constellation area with greater prominence than they appear on the larger maps. This is secured by omitting the fainter stars and'the historical figures, and by connecting the stars by guiding lines.

The educational purpose of the atlas has caused the retention of the outlines of the historical figures, which are usually omitted on professional atlases. They are given in merest outline and for the older constellations of the northern sky only, because of frequent allusions to them in literature. Similar figures were supplied by those astronomers of the eighteenth and nineteenth centuries who completed the system of constellations in the southern hemisphere, but they were added when the use of the figures was becoming obso lete; they are of decidedly inferior character-in their subjects, since they include such mechanical objects as air-pump, clock, telescope, chemical furnace; and they have no place in literature. For these reasons they are not reproduced.

The purpose of the atlas required its preparation according to the best astronomical authorities of to-day. The prevailing usage of modern astronomers has been the criterion adopted; where usage varies, a decision was necessary, and it has been made with great care. The only place where any serious difficulty has arisen has been the proper location of the boundaries between the constellation areas, in which there is no general agreement.

About the Publisher

Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com

This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.