Produced by Suzanne Lybarger, Linda Cantoni, and the Online Distributed Proofreading Team at http://www.pgdp.net (This file was produced from images generously made available by The Internet Archive/Canadian Libraries, http://www.archive.org/details/gradualacceptan00stim) [Transcriber's Note: Obvious printer errors have been corrected without note. Other questionable items are marked with a [Transcriber's Note].] The Gradual Acceptance OF THE Copernican Theory of the Universe DOROTHY STIMSON, Ph.D. NEW YORK 1917 COPYRIGHT 1917 BY DOROTHY STIMSON Trade Selling Agents The Baker & Taylor Co., 354 Fourth Ave., New York TO MY FATHER AND MOTHER [Illustration: THE SYSTEMS OF THE WORLD IN 1651 ACCORDING TO FATHER RICCIOLI (Reduced facsimile of the frontispiece in Riccioli: _Almagestum Novum_. Bologna, 1651.)] EXPLANATION "Astrea, goddess of the heaven, wearing angel's wings and gleaming everywhere with stars, stands at the right; on the left is Argus of the hundred eyes, not tense, but indicating by the position of the telescope at his knee rather than at the eyes in his head, that while observing the work of God's hand, he appears at the same time to be worshipping as in genuflexion." (Riccioli: _Alm. Nov._, _Præfatio_, xvii). He points to the cherubs in the heavens who hold the planets, each with its zodiacal sign: above him at the top is Mars, then Mercury in its crescent form, the Sun, and Venus also in the crescent phase; on the opposite side are Saturn in its "tripartite" form (the ring explanation was yet to be given), the sphere of Jupiter encircled by its four satellites, the crescent Moon, its imperfections clearly shown, and a comet. Thus Father Riccioli summarized the astronomical knowledge of his day. The scrolls quote Psalms 19:2, "Day unto day uttereth speech and night unto night showeth knowledge." Astrea holds in her right hand a balance in which Riccioli's theory of the universe (an adaptation of the Tychonic, see p. 68) far outweighs the Copernican or heliocentric one. At her feet is the Ptolemaic sphere, while Ptolemy himself half lies, half sits, between her and Argus, with the comment issuing from his mouth: "I will arise if only I am corrected." His left hand rests upon the coat of arms of the Prince of Monaco to whom the _Almagestum Novum_ is dedicated. At the top is the Hebrew _Yah-Veh_, and the hand of God is stretched forth in reference to the verse in the Book of Wisdom (10:20): "But thou hast ordered all things in measure, and number and weight." CONTENTS ILLUSTRATIONS 7 PREFACE 8 PART I. AN HISTORICAL SKETCH OF THE HELIOCENTRIC THEORY OF THE UNIVERSE. Chapter I. The Development of Astronomical Thought to 1400: Preliminary Review 9 Chapter II. Copernicus and his Times 20