BY THE SAME AUTHOR.

POPULAR LECTURES ON SCIENTIFIC SUBJECTS.

TRANSLATED BY

E. ATKINSON, Ph.D., F.C.S.

With 68 illustrations. 2 volumes. Crown 8vo, 3s. 6d. each.

CONTENTS.

Volume I.—The Relation of Natural Science to Science in General—Goethe's Scientific Researches—The Physiological Causes of Harmony in Music—Ice and Glaciers—The Interaction of the Natural Forces—The Recent Progress of the Theory of Vision—The Conservation of Force—The Aim and Progress of Physical Science.

Volume II.—Gustav Magnus: In Memoriam—The Origin and Significance of Geometrical Axioms—The Relation of Optics to Painting—The Origin of the Planetary System—Thought in Medicine—Academic Freedom in German Universities—Hermann von Helmholtz: an Autobiographical Sketch.

LONGMANS, GREEN AND CO.,

LONDON, NEW YORK, BOMBAY, AND CALCUTTA.