INTRODUCTION
The sole purpose of this book is to afford a convenient guide for the amateur astronomer when engaged in telescopic observation.
Aside from a study of the moon's surface, the observation of double stars is sure to prove the most attractive work for the possessor of a small telescope. The brighter doubles the novice will have no difficulty in finding, but those below the third magnitude are often difficult to locate without reference to a diagram of the constellation of which it is a part—hence the author has seen fit to place such a diagram where it can be easily consulted.
It is presupposed that the owner of the telescope is familiar with the constellations. It then should be an easy matter, with the assistance of the accompanying diagrams, to find the double stars mentioned in the text.
The constellations are grouped under the seasons for the sake of convenience.
Many of the stars have faint companions of the ninth, tenth, or fainter magnitudes, These doubles are interesting solely to those who desire to test their eyesight, or the powers of their glass. They are disappointing as compared with the beautiful doubles the magnitude of whose components are more nearly on a par, such as
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