“Professor Thurston almost exhausts his subject; details of mechanism are followed by interesting biographies of the more important inventors. If, as is contended, the steam-engine is the most important physical agent in civilizing the world, its history is a desideratum, and the readers of the present work will agree that it could have a no more amusing and intelligent historian than our author.”—Boston Gazette.

STUDIES IN SPECTRUM ANALYSIS. By J. Norman Lockyer, F. R. S., Correspondent of the Institute of France, etc. With 60 Illustrations. 12mo, cloth, $2.50.

“The study of spectrum analysis is one fraught with a peculiar fascination, and some of the author’s experiments are exceedingly picturesque in their results. They are so lucidly described, too, that the reader keeps on, from page to page, never flagging in interest in the matter before him, nor putting down the book until the last page is reached.”—New York Evening Express.

GENERAL PHYSIOLOGY OF MUSCLES AND NERVES. By Dr. I. Rosenthal, Professor of Physiology at the University of Erlangen. With seventy-five Woodcuts. (“International Scientific Series.”) 12mo, cloth, $1.50.

“The attempt at a connected account of the general physiology of muscles and nerves is, as far as I know, the first of its kind. The general data for this branch of science have been gained only within the past thirty years.”—Extract from Preface.

SIGHT: An Exposition of the Principles of Monocular and Binocular Vision By Joseph Le Conte, LL. D., author of “Elements of Geology”; “Religion and Science”; and Professor of Geology and Natural History in the University of California. With numerous Illustrations. 12mo, cloth, $1.50.

“It is pleasant to find an American book which can rank with the very best of foreign works on this subject. Professor Le Conte has long been known as an original investigator in this department; all that he gives us is treated with a master-hand.”—The Nation.

ANIMAL LIFE, as affected by the Natural Conditions of Existence. By Karl Semper, Professor of the University of Würzburg. With 2 Maps and 106 Woodcuts, and Index. 12mo, cloth, $2.00.

“This is in many respects one of the most interesting contributions to zoölogical literature which has appeared for some time.”—Nature.

THE ATOMIC THEORY. By Ad. Wurtz, Membre de l’Institut; Doyen Honoraire de la Faculté de Médecine; Professeur à la Faculté des Sciences de Paris. Translated by E. Cleminshaw, M. A., F. C. S., F. I. C., Assistant Master at Sherborne School. 12mo, cloth, $1.50.