The Project Gutenberg eBook of A Popular History of Astronomy During the Nineteenth Century, by Agnes M. (Agnes Mary) Clerke

Title: A Popular History of Astronomy During the Nineteenth Century

Fourth Edition

Author: Agnes M. (Agnes Mary) Clerke

Release Date: March 4, 2009 [eBook #28247]

Language: English

Character set encoding: ISO-8859-1

***START OF THE PROJECT GUTENBERG EBOOK A POPULAR HISTORY OF ASTRONOMY DURING THE NINETEENTH CENTURY***

E-text prepared by Eric Hutton
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TRANSCRIBER'S NOTE

Typographical errors noticed during the preparation of this text have been underlined like this. A list has also been placed at the end.

A POPULAR HISTORY OF ASTRONOMY

DURING THE NINETEENTH CENTURY

BY THE SAME AUTHOR

A. AND C. BLACK, SOHO SQUARE, LONDON, W.

THE GREAT NEBULA IN ORION, 1883
See p. 408

A POPULAR

HISTORY OF ASTRONOMY

DURING

THE NINETEENTH CENTURY

BY

AGNES M. CLERKE

JUPITER 1879 SATURN 1885

LONDON
ADAM AND CHARLES BLACK
1908

First Edition, Post 8vo., published 1885

Second Edition, Post 8vo., published 1887

Third Edition, Demy 8vo., published 1893

Fourth Edition, Demy 8vo., published 1902

Fourth Edition, Post 8vo., reprinted February, 1908

PREFACE TO THE FOURTH EDITION

Since the third edition of the present work issued from the press, the nineteenth century has run its course and finished its record. A new era has dawned, not by chronological prescription alone, but to the vital sense of humanity. Novel thoughts are rife; fresh impulses stir the nations; the soughing of the wind of progress strikes every ear. "The old order changeth" more and more swiftly as mental activity becomes intensified. Already many of the scientific doctrines implicitly accepted fifteen years ago begin to wear a superannuated aspect. Dalton's atoms are in process of disintegration; Kirchhoff's theorem visibly needs to be modified; Clerk Maxwell's medium no longer figures as an indispensable factotum; "absolute zero" is known to be situated on an asymptote to the curve of cold. Ideas, in short, have all at once become plastic, and none more completely so than those relating to astronomy. The physics of the heavenly bodies, indeed, finds its best opportunities in unlooked-for disclosures; for it deals with transcendental conditions, and what is strange to terrestrial experience may serve admirably to expound what is normal in the skies. In celestial science especially, facts that appear subversive are often the most illuminative, and the prospect of its advance widens and brightens with each divagation enforced or permitted from the strait paths of rigid theory.

This readiness for innovation has undoubtedly its dangers and drawbacks. To the historian, above all, it presents frequent occasions of embarrassment. The writing of history is a strongly selective operation, the outcome being valuable just in so far as the choice what to reject and what to include has been judicious; and the task is no light one of discriminating between barren speculations and ideas pregnant with coming truth. To the possession of such prescience of the future as would be needed to do this effectually I can lay no claim; but diligence and sobriety of thought are ordinarily within reach, and these I shall have exercised to good purpose if I have succeeded in rendering the fourth edition of A Popular History of Astronomy during the Nineteenth Century not wholly unworthy of a place in the scientific literature of the twentieth century.

My thanks are due to Sir David Gill for the use of his photograph of the great comet of 1901, which I have added to my list of illustrations, and to the Council of the Royal Astronomical Society for the loan of glass positives needed for the reproduction of those included in the third edition.

London, July, 1902.

PREFACE TO THE FIRST EDITION

The progress of astronomy during the last hundred years has been rapid and extraordinary. In its distinctive features, moreover, the nature of that progress has been such as to lend itself with facility to untechnical treatment. To this circumstance the present volume owes its origin. It embodies an attempt to enable the ordinary reader to follow, with intelligent interest, the course of modern astronomical inquiries, and to realize (so far as it can at present be realized) the full effect of the comprehensive change in the whole aspect, purposes, and methods of celestial science introduced by the momentous discovery of spectrum analysis.

Since Professor Grant's invaluable work on the History of Physical Astronomy was published, a third of a century has elapsed. During the interval a so-called "new astronomy" has grown up by the side of the old. One effect of its advent has been to render the science of the heavenly bodies more popular, both in its needs and in its nature, than formerly. More popular in its needs, since its progress now primarily depends upon the interest in, and consequent efforts towards its advancement of the general public; more popular in its nature, because the kind of knowledge it now chiefly tends to accumulate is more easily intelligible—less remote from ordinary experience—than that evolved by the aid of the calculus from materials collected by the use of the transit-instrument and chronograph.

It has thus become practicable to describe in simple language the most essential parts of recent astronomical discoveries, and, being