SCIENCE 



New Seeies. 

 Vol. IV. No. 83. 



Fkiday, July 31, 1896. 



Single Copies, 15 cts. 

 Annual Subscription, go.OO. 



The JVIacmillan Company's New Books. 



JUST BEADY. 



THE PRINCIPLES OF THE TRANSFORMER. 



By De. FEEDEEICK BEDELL, of Cornell University. 



svo. Cloth, $3.25 net. 



This book contains an extensive treatment of the laws and principles governing the operation of the 

 transformer. A feature of the work is the unity and sequence of treatment, the method of treatment being 

 such as to make it valuable to the practicing engineer as a work of reference, and to the student as a text- 

 book. The book contains chapters on Transformer Systems of Distribution, the Design and Construction of 

 Transformers, Constant Current and Constant Potential Transformers, the simple theory and the general 

 theory of Transformers, effects of hysteresis and foncault currents, Transformer Diagrams and Transformer 

 Testing. Graphical methods are freely employed. The book contains about 400 pages with over 200 

 illustrations. 



Lectures on Human and Animal 



Psychology. 



By WiLHELM WuNDT, Professor of Philosophy in the 

 University of Leipzig. Translated from the 

 Second German Edition by J. E. Creighton and 

 E. B. Titchener. Second Edition of Translation 

 Eevised. 8vo, cloth, |2.60 net. 



The Biological Problem of To=Day. 



Preformation or Epigenesis. The Basis of a Theory 

 of Organic Development. By Professor Dr. 

 OscAE Heetwig, Director of the Second Ana- 

 tomical Institute of the University of Berlin. 

 Authorized Translation by P. Chalmers Mitchell, 

 M.A., with an Introduction by the Translator, 

 and a Glossary of the Technical Terms. 16mo, 

 cloth, $1.25. 



JUST HEADY. 



AN OUTLINE OF PSYCHOLOGY. 



By EDWAED BEADFOED TITCHNEE, A.M., Ph.D. 

 Sage Professor of Psychology at Cornell University. Co-editor of "3Iind,^^ and of the "American Journal of 



Psychology.^' 



CROWN 8vo, Cloth, 91. SO NET. 



Modern Optical Instruments and Their 

 Construction. 



By Heney Oefoed. Author of "Lens Work for 

 Amateurs." With illustrations. 16mo, cloth, 

 80 cents. 



Engineer's Draughtsman's Work. 



Hints for Beginners. By a Practical Draughtsman. 

 With illustrations iy the Author. 16mo, cloth, 60 

 cents. 



JSfew Book by Sir JOHN LUBBOCK— Now Ready : 



The Scenery of Switzerland, and the Causes to which it is Due. 



By the Eight Hon. Sir JOHN LUBBOCK, Bart., M.P., F.E. S., D.C.L., LL.D. With numerous 

 Plans and Illustrations. Crown Bvo, $1.50. 

 By the same Author, Uniform with the above : 



The Beauties of Nature. 



And the Wonders of the World we 

 Live In. With numerous Illus- 

 trations. 3d Edition. 12mo, 

 cloth, $1.50. 



The Pleasures of Life. 



Two Parts. Complete in one vol 

 ume. 12mo, cloth, $1.25. 



The Use of Life, 



12mo, cloth, $1.25. 



THE riACMILLAN COMPANY, 66 Fifth Avenue, New York City. 



