Page 572 - 89 history of astronomy_opt
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globe, there remains an innumerable host
                                         of fixed stars, nebulas, and nebulous clus-
                                         ters of stars. To these the attention of as-
                                         tronomers has been more earnestly directed
                                         since telescopes have been so much enlarged.
                                         Photography also has enabled a vast amount
                                         of work to be covered in a comparatively
                                         short period, and the spectroscope has given
                                         them the means, not only of studying the
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