for the Reference Library their Adulterations 42 Illustrations. 8vo, xv+421 Pages. Cloth, $3.50 Postpaid. The Origin, Composition, Manufacture, Natural, Artificial, Fermented, Distilled, Alkaloidal and Fruit Juices. By HARVEY W. WILEY, M.D., formerly Chief of Department of Chemistry, U. S. Bureau of Agriculture; Author of "Foods and Their Adulteration." FROM THE PREFACE: The rapidly increasing use of fruit juices demands a prominent place in this volume, for their description and composition. The many socalled soft drinks which will undoubtedly have a greater vogue as the area in which alcoholic beverages are manufactured and sold decreases; warrant a rather full description of them here. The so-called medicines which consist chiefly of alcohol, and which are held by the Bureau of Internal Revenue as non-medicinal, but alcoholic, are fully described. Proper space is given to a discussion of coffee, and related products, tea, cocoa, chocolate. Water with potable waters, mineral waters, artificial and natural, are included. With each subject treated are described the common adulterations and misbrandings which may be practiced therewith. P. Blakiston's Son & Co., Philadelphia Cooking Class at the South Dakota State College are using GAS made by Combination Gas Machine for supplying gas in Departments of Domestic Science Chemistry and Physics (Over 30,000 in daily use) Laboratory work can be done better, quicker and cheaper by using this gas. Ask for descriptive catalog and names of users in your vicinity. Detroit Heating & Lighting Co. 612 Wight St. Detroit, Mich. Est. 1868 Northrup Millivolter Made under the Pyrovolter Patents of November 6, 1917 The new NORTHRUP MILLIVOLTER is a standardized portable deflection potentiometer, working on the Pyrovolter Principle. This instrument offers a convenient means for the accurate measurement of e.m.f.s. up to one volt, without the abstraction of any current from the source of the e.m.f. being measured. The MILLIVOLTER should generally be used in place of a millivoltmeter, where accuracy is of importance. It is valuable for taking the voltage drop in motors, for the measurement of low voltages over electrolytic baths where a carefully measured current is flowing, for use in thermocouple pyrometry, for measuring the internal resistance of dry cells, and for accurate measurement of large currents by reading the voltage drop over a low known resistance. The MILLIVOLTER has one hand-drawn scale and three ranges: 0-10 mv., 0-100 mv., and 0-1000 mv. It is described in Circular No. 9, which awaits your request. In Preparation EDUCATIONAL PSYCHOLOGY By DANIEL STARCH, Ph.D., Associate Professor of Psychology and Education, The preparation of this book has been in accordance with two fundamental purposes. It aims to present that material which is most useful and relevant to the problems of educational psychology, and to maintain a strictly experimental, scientific point of view in discussing these problems. As a result, less space has been devoted to traditional material than is usually the case in texts on educational psychology, thus making possible the introduction of new topics such as tests of intelligence, studying, transfer of training in school subjects, the assignment of marks, and particularly a comprehensive survey of the experimental work on the psychology of school subjects. TABLE OF CONTENTS Problems of Educational Psychology. Part I. The Native Equipment of Human Beings. What it Consists of. Variation in Human Capacities: (a) In Single Traits; (b) In Combinations of Traits; (c) Between the Sexes. Inheritance of Mental Traits. Measurement of the Mental Equipment of Human Beings. Part II. The Psychology of Learning: (A) In General. Analysis of Problems. The Reception of Stimuli: (a) Sensory Defects; (b) Perception and Observation. Rate and Progress of Learning. How to Study. Transference of Training: In Specific Mental Functions; In Abilities in School Subjects. Part III. The Psychology of Learning: (B) Of School Subjects. The Psychology of Learning School Subjects. Reading. Writing. Spelling. Language, Arithmetic, History. Marks as Measures of School Work. QUANTITATIVE ANALYSIS By GEORGE MCPHAIL SMITH, Assistant Professor of Chemistry in the Univer- Both the classroom and laboratory work in Quantitative Chemical Analysis are carefully provided for in this introductory course. In dealing with the laboratory side the primary intent of the work is to afford the student directions sufficiently detailed to enable him to work successfully without an undue amount of personal supervision. The instructor is thereby placed in a position, in the laboratory as well as in the classroom, to exert his personal influence more especially toward the development of theoretical knowledge and independent thought on the part of the student. The analyses selected for practice, included in Parts II and III, are those which during several years of use in introductory courses, have proved to be satisfactory types of gravimetric and volumetric analysis. Part IV contains stoichiometrical problems which will give the student an insight into the principles of a wide variety of processes. THE MACMILLAN COMPANY PUBLISHERS NEW YORK K K We have long endeavored to produce Laboratory Furniture superior to any other in America. We have spent much time and money in developing a line that adequately fulfills our ambition. You have frequently heard our assurances on this point, and it may interest you to know that by far our greatest volume of business each year now comes from schools supervised by educators who have known Kawaunee equipment elsewhere. Kewaunee LABORATORY FURNITURE We might put it this way: That our best advertising and sales argument is the Furniture itself. Besides telling the truth about the leading line of Laboratory Furniture, our new Book presents hundreds of spontaneous expressions from educators who are personally familiar with its record in the class room. It will interest you. Kewaunee Mfg. Co. LABORATORY MONOGRAPHS ON EXPERIMENTAL BIOLOGY AND GENERAL PHYSIOLOGY The publishers take much pleasure in announcing a new series of monographs covering the subjects of experimental biology and general physiology. These volumes will be under the general editorship of Jacques Loeb, T. H. Morgan, and W. J. V. Osterhout. NOW READY The Elementary Nervous System By G. H. PARKER, Sc.D., Professor of Zoology, Harvard University. The dependence of human affairs upon the nervous system of man is so absolute that it was inevitable, as soon as this relation was understood, that the activities of the simpler animals should be interpreted as though these creatures were miniature human beings. That such interpretation was carried far beyond its legitimate bounds, even by the scientifically trained, is now admitted on almost all sides, but it is no easy or simple task to ascribe to this movement its proper bounds. That these bounds are vastly more restricted than has usually been supposed is certain. An approach to a clearer understanding of what they are is assured through the application of experimental and quantitative methods to the questions concerned rather than by a continuation of the older more purely observational procedure. It is from this standpoint that an attempt has been made in this volume to portray the elementary nervous system as it exists in the simpler animals and in the simpler parts of the more complex forms. Forced Movements, Tropisms, and Animal Conduct By JACQUES LOEB, M.D., Ph.D., Sc.D., Member of the Rockefeller Institute for Animal conduct is known to many through the romantic tales of popularizers, through the descriptive work of biological observers, or through the attempts of vitalists to show the inadequacy of physical laws for the explanation of life. Since none of these contributions are based upon quantitative experiments, they have led only to speculations, which are generally of an anthropomorphic or of a purely verbalistic character. It is the aim of this monograph to show that the subject of animal conduct can be treated by the quantitative methods of the physicist, and that these methods lead to the forced movements or tropism theory of animal conduct, which has only recently been carried to some degree of completion. IN PREPARATION THE CHROMOSOME THEORY OF HER- INBREEDING AND OUTBREEDING: Their PURE LINE INHERITANCE. By H. S. THE NATURE OF ANIMAL LIGHT. By PERMEABILITY AND ELECTRICAL CON- THE EQUILIBRIUM BETWEEŇ ACIDS By CHEMICAL BASIS OF GROWTH. By T. J. B. LIPPINCOTT COMPANY CHICAGO BOSTON ATLANTA MONTREAL LONDON BARNSTEAD AUTOMATIC WATER DISTILLING APPARATUS 26516. Distilling Apparatus, Barnstead, for gas heating, with adjustable burner permitting the use of any kind of gas. Distilling Apparatus, Barnstead, for electric heating, with switch and pilot board. As re- 1 2 NOTE-We supply Barnstead Stills for gas heating in 10 gal. per hour capacity; Barnstead Copy of new Supplement No. 50, "Stokes and Barnstead Automatic ARTHUR H. THOMAS COMPANY IMPORTERS-DEALERS-EXPORTERS LABORATORY APPARATUS AND REAGENTS WEST WASHINGTON SQUARE PHILADELPHIA, U. S. A. |