Excerpt from The Combination of Observations I have to acknowledge my indebtedness to Mr F. J. M. Stratton, Of Gonville and Caius College, Cambridge, to whose University lectures I owe most Of my knowledge of the subjects discussed in this book, and upon whose notes I have drawn freely. I have also to thank Professor Eddington for many useful suggestions made while the book was in manuscript form, and for permission to extract from his lecture notes a number Of interesting examples as well as some portions Of the theoretical treatment. I cannot express adequately my debt to the Cambridge University Press, for the extreme care shown in passing the book through the proof stage. Owing to my being abroad at the time, I was not able to devote as much time as was desirable to the reading Of proofs, and but for the unfailing vigilance of the Press, many errors would have been allowed to pass into the text. 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.