LONGMAN'S PUBLICATIONS NEW EDITION OF THORPE'S DICTIONARY OF CHEMISTRY A DICTIONARY OF APPLIED CHEMISTRY By SIR EDWARD THORPE, C.B., LL.D., F.R.S., Emeritus Professor of General Chemistry and Director of the Chemical Laboratories of the Imperial College of Science and Technology, South Kensington, London. Assisted by Eminent Contributors. Vol. I. Revised and Enlarged Edition, with Illustrations. Royal 8vo. $20.00 net Vol. II. will be published early in the Summer, and it is hoped that the work will be completed in about two years. The entire work has been carefully revised in the light of recent developments, and so much new matter included that it has been found necessary to enlarge it; six volumes will certainly be needed, and it is possible that a seventh will be required. MONOGRAPHS ON INDUSTRIAL CHEMISTRY "Those who are responsible for organizing this valuable series may well be congratulated on this wealth of material illustrating the applications of recent scientific knowledge to modern manufacture."-THE LANCET. A Prospectus of the Series will be mailed on application. Volumes Already Issued. ORGANIC COMPOUNDS OF ARSENIC AND AN- FACTORY CHEMISTRY Preparatory to Courses in Metallurgy and Metallography. By WM. H. HAWKES, A.B., M.Sc. Department of Chemistry Ford Institute of Technology, Detroit, Michigan. 12mo. $1.00 This text is especially designed for factory men interested in the study of chemistry as it bears on the various operations in factory processes, presenting by simple, clear and rapid methods that part of chemical science which will be of daily use and practical value in departments where a knowledge of chemistry is of advantage and often indispensable. HEAT ENGINES. Embracing the Theory, Construction, and Performance of Steam Boilers, Reciprocating Steam Engines, Steam Turbines, and Internal Combustion Engines. A Text-book for Engineering Students. By DAVID ALLAN LOW. With 656 Illustrations and 315 Exercises. 8vo. $6.50 net NEW AND REVISED EDITIONS ORGANIC CHEMISTRY FOR ADVANCED STUDENTS. By JULIUS B. COHEN. In three Parts. 8vo. Each $6.50 net $7.50 net THE TESTING OF MOTIVE-POWER ENGINEERS. By R. ROYDS. With 193 Diagrams. 8vo. REINFORCED CONCRETE DESIGN. By OSCAR FABER, and P. G. BOWIE. Vol. I. Theory. 8vo. $5.00 Vol. II. Practice. 8vo. $6.50 net. $6.00. A TEXT-BOOK OF PHYSICS. By W. WATSON. With 580 Diagrams and Illustrations. Crown 8vo. TABLES OF PHYSICAL AND CHEMICAL CONSTANTS, AND SOME MATHEMATICAL FUNCTIONS. G. W. C. KAYE, and T. H. LABY. 8vo. $4.00. By THE CHEMISTRY OF SYNTHETIC DRUGS. By PERCY MAY, 8vo. $4.25 net. ELEMENTS OF MECHANICS. By G. W. PARKER, M.A. With 116 Diagrams and Answers to Examples. 8vo. $3.00 net $4.25 net $3.50 net THE PHYSIOLOGY OF PROTEIN METABOLISM. By E. P. CATHCART. 8vo. RELATIVITY AND THE ELECTRON THEORY. By E. CUNNINGHAM, M.A. With Diagrams. A SYSTEM OF PHYSICAL CHEMISTRY. By WILLIAM C. McC. LEWIS, M.A. 3 vols. 8vo. Vols. 1 and 2, each $5.00 net. Vols. 3, $2.50 net. Send for a Catalogue of Pure and Applied Science LONGMANS, GREEN & COMPANY, Publishers Fourth Avenue and 30th Street, New York PYREX Pyrex Will Cut Down Your Laboratory Glass Bill -It minimizes breakage from mechanical shock -It is highly resistant to sudden heating and cooling -It does not commence to soften below approximately 800°C. Repeated object lessons have demonstrated that nearly all progress in science has resulted in important advances in industry G-E Research Laboratory Schenectady, N. Y. Among the many products developed by the General For further information address Supply Department, Schenectady Office. General Electric General Office Company A close textured filter paper with the highest speed consistent with the retention of fine precipitates. Standardized tests for the control of the manufacture of this paper show it superior in these important characteristics to the best imported papers. The ash averages about 0.016 per cent., which for the 11 cm. size is equivalent to 0.00012 grams per circle. This paper was developed in the laboratories of Arthur D. Little, Inc., and is made on their experimental paper machine, which is operated with distilled water. It is the first high-grade quantitative filter paper to be entirely made in the U. S. and, we believe, is destined to rank with Pyrex chemical glassware and Coors laboratory porcelain ware in its importance as an American product for which chemists in pre-war years were entirely dependent on foreign factories. 10 per cent. discount in cartons of 100 boxes of a size. Sample packets of six 11 cm. circles sent free on request ARTHUR H. THOMAS COMPANY WHOLESALE, RETAIL AND EXPORT MERCHANTS LABORATORY APPARATUS AND REAGENTS WEST WASHINGTON SQUARE PHILADELPHIA, U. S. A. THE DUTY OF SCIENTIFIC MEN IN CONSERVATION 1 THE Conservation movement of a few years ago crystallized and brought to public attention a great principle, one so far reaching that its real significance and scope are even to-day not generally grasped. Regardless of how the term may be defined, the problem of conservation involves the whole question of the relation of our natural resources to the economic life and upbuilding of the country. We have to do not merely with the prevention of waste and economical use of our resources, but also with the problem of how these resources may render their highest service in building up local communities, maintaining our industries, and contributing to a strong civilization. We can point to considerable progress in certain features of conservation during the past decade. Scientific men have conducted research of great value that already is resulting in new uses of various raw materials, in more economical methods of handling them, and in improved methods of perpetuating those resources which are renewable; engineers are giving more attention than formerly to the problem of preventing unnecessary losses in the exploitation of raw resources; the more far-sighted leaders of industry have an increasing appreciation of the relation of natural resources to the permanence of their own enterprises. And yet, the conservation principle is making slow headway, when viewed from the larger aspects of the economic needs of the country. The loss through unnecessary waste is still appalling, uneconomic methods in the use and development of various 1 This paper was presented at a joint meeting on April 9, of three Committees on Conservation, representing the National Academy of Sciences, the National Research Council, and the American Association for the Advancement of Science. |