The above titles represent University of California Publications in Agricultural Sciences, American Archaeology and Ethnology, Geology and Zoology. Other series published by the University of California include: Botany, Entomology, Geography, Pathology, Physiology and Psychology. Complete Lists of Titles and Prices will be sent on Request The Philippine Journal of Science ALVIN J. COX, M.A., Ph.D., General Editor of the Government of the Plant Physiology. ROBBINS-Botany of Crop Plants. REESE-Economic Zoology P. Blakiston's Son & Co., Philadelphia Published on June 20 Carnegie Pensions By J. McKEEN CATTELL Together with Extracts from Letters from Two Hundred and Fourteen College and University Professors, an Article on the History of the Carnegie Foundation by Joseph Jastrow, and the Reports of the Committee on Pensions and Insurance of the American Association of University Professors. Pages viii+253. Price, $1.50 Postpaid THE SCIENCE PRESS GARRISON NEW YORK Educational Psychology By DANIEL STARCH, Ph.D., Associate Professor of Psy- "The aim of education is to change human beings for the better so that they will have more humane and useful wants, and be more able to satify them.' In his new text-book, "Educational Psychology," Professor Starch uses th s definition by Thorndike as his point of departure. He considers the fundamental problems of educational psychology to be the determination of the capacities which human beings possess for acquiring the changes, and the investigation and evaluation of methods by which these changes may be brought about; accordingly, he recognizes two large divisions in the field of educational psychology; first, the native equipment of human beings; secondly, the psychology of learning. The book treats these two major subdivisions separately; the first includes considerations of the nature of human capacities, variation and inheritance of mental traits, and measurement of mental equipment, the second deals with the physiological and more strictly psychological aspects. An extensive third part considers in detail the problems and practices of schools, and gives special attention to each of the subjects commonly taught. In Preparation Vertebrate Zoology By HORATIO H. NEWMAN, Ph.D., Associate Professor of TABLE OF CONTENTS Chapters: I - Principles of Vertebrate Morphology. II - The Phylum Chordata. III-The Origin and Evolution of the Vertebrates. VIII-Aves. V- Pisces. IX-Mammalia. This volume is intended for use as a text-book in college courses in vertebrate zoology and comparative anatomy. Professor Newman approaches his subject from the dynamic rather than the structural po'nt of view; thus the physiological, phylogenetic, ecological, and evolutionary aspects of vertebrates are particularly emphasized; but careful attention is also given to anatomical facts and data. The book is written in the light of the most recent advances in biology, making use of important new conceptions and experimental evidence bearing upon the evolution and comparative study of vertebrates. THE MACMILLAN COMPANY PUBLISHERS NEW YORK TH HIS is a scientific treatise designed for advanced students and the professions, embracing the natural sexual impulse, normal sexual habits, and propagation, together with sexual physiology and hygiene. The author presents the subject of sex from the normal and physiological-most other books on this subject are written from the abnormal and pathological standpoints. ¶ Physicians are finding it necessary to give advice on sex problems to their patients at the present time more than ever before. Prudery with reference to sexual matters has been relegated to the past-sane, wholesome, scientific information on the sex problems is being demanded by the people of their physician, and the physician must be able to render this service when called upon. "The Sexual Life" is a book that will give you this information. Its wide popularity is attested to by the fact that more than 100,000 copies have been printed. When a book reaches a sale of this size it is evident that it has rendered a service -the unworthy and loosely written text cannot survive. ¶ This book contains chapters on the following subjects: Sexual Sense, Sexual Passion, Female Sexual Sense, Male Sexual Sense, The Copulative Function, The Act of Copulation, Sexual Habits in the Married, Hygienic Sexual Relations, Sexual Inequality, Copulation and Propagation, Nervous Women. NOTE.-The sale of this book is limited to members of the medical, dental, scholastic, legal and clerical professtons. When ordering attach your card or professional letterhead to the accompanying coupon. No need of writing-just sign the attached coupon and mail, but do it today -right now-before you lay down this magazine. C. V. MOSBY CO.-Publishers Medical-Dental-Surgical-Nursing Books Cut Here (Science) C. V. MOSBY CO. St. Louis Please send me a copy of Malchow-"The Sexual Life," for which I enclose my check for $3.00. Name 801-809 Metropolitan Building THE BROOKS' INDUCTOMETER In the Brooks' Inductometer is offered a compact form of variable inductance, with a self inductance range of 5 to 50 millihenrys, possessing the following advantages: 1. A fair degree of astaticism, which tends to eliminate errors due to stray field effects. 2. It is less expensive and at the same time fully as accurate as the AyrtonPerry instrument. 3. It occupies less space than the Aryton-Perry form. The instrument has a very nearly uniform scale, obtained by properly proportioning the coils. It may be used as a mutual inductance. It has a good ratio of maximum to minimum inductance (about 9 to 1) and also has as high a time constant as is consistent with good design and moderate size. The instrument is fully described in Bulletin No. 152, a copy of which will be sent upon request. THE LEEDS & NORTHRUP CO. ELECTRICAL MEASURING INSTRUMENTS 4921 STENTON AVENUE PHILADELPHIA Langmuir Condensation Pump Dr. Irving Langmuir (of the General Electric Co.) has developed an exceedingly interesting and valuable high-speed high-vacuum pump, and by special agreement with the makers, we are acting as sole distributors, for laboratory With this pump pressure as low as 10-5 bar have been obtained; and there is little doubt that very much lower pressures can be produced, by cooling the bulb to be exhausted, in liquid air, so as to decrease the rate at which gases escape from the walls. Some type of primary pump must be used; capable of developing a vacuum not less than 0.1-0.15 mm.of mercury. The illustration shows a Langmuir pump, connected to a two-stage primary oil pump-which is operated by a HP motor; all three parts of the outfit being assembled together on one base. JAMES G. BIDDLE 1211-13 ARCH STREET PHILADELPHIA If interested, write for copy of illustrated Bulletin 881, issued November, 1917; and also copy of paper by Dr. Langmuir. PULFRICH REFRACTOMETER AS MADE BY ADAM HILGER, Ltd., LONDON IN OUR STOCK FOR IMMEDIATE SHIPMENT No. 45829 Pulfrich Refractometer, Hilger make 45829. REFRACTOMETER, PULFRICH, Hilger's latest model, for the measurement of refractive indices of both solids and liquids to an accuracy of about 0.0001, and the dispersion, i. e. the difference of refractive index for two spectral lines, to about 0.00002 in the interval 1.33 to 1.73. With prism of refractive index D. of 1.74 for substances of refractive indices for D. between 1.47 and 1.73 with mount and carrier and improved water jacketing attachments. In case with lock and key. Stock ... 45833. Hydrogen End-on Vacuum Tube, for use with Pulfrich Refractometer No. 45829. 10.15 555.00 . . 13.90 Duty Free. 45837. Prism of refractive index for D. of about 1.62 for liquids of refractive indices for D. between 1.33 and 1.61 with mount and carrier and with glass cell for liquids. Duty Free ... . . . 27.00 Stock. 37.00 Orders accepted for duty free importation with delivery in from twelve to fifteen weeks. All prices subject to change without notice. ARTHUR H. THOMAS COMPANY IMPORTERS-DEALERS-EXPORTERS LABORATORY APPARATUS AND REAGENTS WEST WASHINGTON SQUARE PHILADELPHIA, U. S. A. |