THE present volume originated in a desire to present, in small compass, a record of the marvellous progress in astronomy during the past hundred years. Indebtedness should be acknowledged to the valuable works of Professor Newcomb, Professor Schiaparelli, Professor Lowell, Professor Young, Sir Robert Ball, Mr Gore, M. Flammarion, and Miss Clerke, who, as the historian of modern astronomy, occupies a place at once authoritative and unique.

THE following work is translated and abridged from M. Flammarion's LJ 'Atmosphere, Paris, 1872. That some curtailment of the text of the original work was requisite will be apparent when it is stated that the French Edition contains 824 large pages of closely printed matter, and is of more than twice the extent of the present volume. Not only was some compression necessary in order to bring the work within a reasonable compass, but, independently of this, one or two chapters, such as that on the Eespiration and Alimentation of Plants, appeared to have so remote a connection with the subject of the work the Atmosphere that their omission would in any case have been desirable.

SIR WILLIAM ROWAN HAMILTON, the eminent mathematician of Dublin, has, of all writers ancient and modern, most fittingly characterized the ideal science of astronomy as man's golden chain connecting the heavens to the earth, by which we "learn the language and interpret the oracles of the universe."

The oldest of the sciences, astronomy is also the broadest in its relations to human knowledge and the interests of mankind...

THE present volume has been prepared with a double purpose, and upon a plan somewhat unusual. First, an effort has been made to meet the wishes of the rdinary reader who may desire to inform himself as to the present state of astronomic science, or to secure a simple explanation of the many phenomena constantly exhibiting themselves in the universe about him ; and the further purpose has been to produce a satisfactory textbook for use in high schools and colleges.

THE object of this book is to give an account of the science of Astronomy, as it is known at the present day, in a manner acceptable to the general reader.

THE present treatise is a condensed edition of the Astronomy of the American Science Series. The book has not been shortened by leaving out anything that as essential, but by omitting some of the details of practical astronomy, thus giving to the descriptive portions a greater relative extension.

I MUST PREFACE these pages by a few words of explanation. The decay of my eye-sight has within the last year incapacitated me from reading or writing. Cut off by this affliction from my usual mental employments, I have found relief and occupation to my thoughts in dictating these essays to a short-hand riter. This mode of writing will excuse any inaccuracies or mistakes which I may have committed.

WAEFIELD PARK, BRACKNELL:
December 1, 1871.

ASTRONOMY, it has been said, is the oldest and the noblest of the sciences. Yet it is one of the few sciences for which most present-day educators seem to find little, if any, room in their curriculum of study for the young, in spite of its high cultural value. It is, we are told, too abstruse a subject for the youthful student. This is doubtless true of theoretical or mathematical astronomy and the practical astronomy of the navigator, surveyor and engineer, but it is not true of general, descriptive astronomy. There are many different aspects of this many-sided science, and some of the simplest and grandest truths of astronomy can be igrasped by the intelligent child of twelve or fourteen years of age...