Excerpt from The Astrophysical Journal, Vol. 23: An International Review of Spectroscopy and Astronomical Physics Minor contributions and notes: Determination of Radial Motions by Objective Prisms, Edward C. Pickering, 255; Stars Having Peculiar Spectra; Thirteen New Variable Stars, Edward C. Pickering, 257; The Spectrum of Nova Aquilae N o. 2, J. H. Moore, 261; A List of F our Stars Whose Radial Velocities are Variable, J. H. Moore, 263; Spectrographic Observations, Edwin B. Frost, 264; Note on the D. O. Mills Expedition to the Southern Hemi sphere, W. W. Campbell, 269. 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.