PREFACE TO THE FIRST EDITION.
The present volume contains a series of sketches of certain parts of astronomy which are now attracting a great deal of attention. I may specially mention among the novel parts of the book Chapters XIII. and XIV., relating to Meteorites. The last chapter, "On the Constitution of Gases," discusses points which seem destined to be of great importance in astronomy, while the first chapter studies, in a new light, the great question of the movement of our system.
Although several of the chapters consist of articles contributed to the Contemporary or the Fortnightly, yet it has been necessary to revise them in accordance with the advance of science. In certain cases considerable alterations have been found necessary. The opportunity has also been taken to provide for the illustration of the articles, which was not possible under the circumstances of their original appearance.
It gives me much pleasure to acknowledge the kindly assistance which has been afforded. I am indebted to Dr. Downing, the Superintendent of the "Nautical Almanac," for permission to reproduce the path of the Eclipse of 1893, to Mr. N. Green for his beautiful drawing of Mars, and to Mr. J. R. Gregory for the photograph of the large meteorite found at Youndegin, West Australia. I must finally express my thanks to my friends, the Rev. Maxwell H. Close and Mr. L. E. Steele, who have read the proofs through.
Observatory, Cambridge,
21st September, 1893.
