Georgetown University SCHOOL OF MEDICINE AND DENTAL DEPARTMENT The Sixty-fourth Session began in September and COT. tinues eight and one-half months. Six-Year Collegiate and Medi. cal Course leading to degrees B.S. and M.D. Practical laboratory work under special instructors, in Anatomy, Physiology, Chemistry, Histology, Pathology and Bacteriology. Ample facilities for clinical experience and practical work in hospitals of city and in the University Hospital, containing in all over 3,000 beds. For particulars address GEORGE M. KOBER, M. D. Edited by James W. Glover, Ph. D., Professor of Mathematics and Insurance, University of Michigan. 620 pages, 6 x 9". Cloth, $3.90 postpaid. Combines in one book all tables required by college. students in mathematics of finance, insurance, statistics.. Important new tables for actuaries, statisticians, biometricians. Logarithms and values of compound interest func-. tions and conversion factors; life insurance, disability in-. surance, joint life, United States life tables; areas, ordinates, second to eighth derivatives of normal curve of error, extensive tables for exponential growth curve. functions. Seven place logarithms from 1 to 100,000. George Wahr, Publisher. Ann Arbor, Michigan.. First-hand knowledge is easily retained. These well-constructed and accurate microscopes are the result of Bausch & Lomb's 70 years of scientific lens-making. Unusually complete line contains models especially suited to school purposes. State your needs and let us sug- Bausch & Lomb Optical Co., Leading American Makers of Pho- that eyes may see better and farther. STUDENTS' MICROSCOPES The "Praxis" Stand is the Student's model pa excellence. Made throughout with the same a curacy and finis as on Watson highest price Stands. A few special poin are:- Standardiz tion so that add tional movemen may be fitted as r quired. Lever fir adjustment. Co structed of tw solid castings ar indestructible. A parts are slotted ar sprung to compe sate for wear. Catalogue of Microscopes and accessories f W. WATSON & SONS, Ltd. 313, High Holborn, London, England Naturalists' Supplies We carry stock for prompt delivery 1. Collecting Utensils. II. Breeding Apparatus and Cages for Living Animals. IV. V. VI. VII. VIII. IX. X. XI. XII. Cabinets, Insect Cases and Lining Material. Magnifiers, Microscopes and Accessories. Explorers' and Collectors' Camp Outfits. Oologists' Supplies. Aquaria. Books and Publications. Chemicals. K-S Museum Cabinets of Glass and Metal New Illustrated Biological Catalog will be sent free of charge upon application THE KNY-SCHEERER CORPORATION Department of Natural Science G. Lagai, Ph.D. 404-410 WEST 27TH STREET, NEW YORK CITY, N. Y. Evolution Working Backward; Atoms of Light; The Little Enemies of Man; The Birthplace of the Eels; The Total Solar Eclipse of September 21; Scientific THE SCIENTIFIC MONTHLY OCTOBER, 1922 THE CONSERVATION AND PROPER UTILIZATION OF OUR NATURAL RESOURCES1 By Dr. BARTON WARREN EVERMANN DIRECTOR OF THE MUSEUM OF THE CALIFORNIA ACADEMY OF SCIENCES THE HE natural resources of the United States are the richest and most varied of any country in the world. It is only necessary to call attention to our great coal and oil fields and natural gas, our varied mineral resources, wonderful forests of hard and soft woods, our multitude of species of wild game mammals and birds and fur-bearing animals, the hundreds of species of useful insectivorous and predaceous birds, and the rich fisheries of our Atlantic, Gulf and Pacific coasts, Great Lakes and other interior waters, to enable us to realize that our country has been exceedingly blessed in this regard. And this very richness of natural resources has had much to do with making us the most short-sighted, the most extravagant and the most wasteful people in all the world. There is not one of our natural resources which, in the beginning of the development of the country, was not handled in very wasteful ways; in numerous instances so wasteful and destructive that the resource was wiped out almost, if not quite, entirely. Such were the Buffalo, Wild Pigeon, Atlantic Salmon, Wild Turkey, Gray Squirrel, Sturgeon, Sea Otter, natural gas, white pine and many others that might be mentioned. It is now too late to do anything to correct the mistakes with some of the species that were once valuable assets to our people, because they are now entirely extinct, or are species whose wellbeing depends upon an environment which has passed and can not be restored. But there are many species of the native flora and fauna with which it is not too late and which, with proper care, 1 Presidential address delivered June 22, 1922, at the Salt Lake City meeting of the American Association for the Advancement of Science. Vol. XV.-19. |