National Geographic : 1912 Jan
THE HOME OF THE NATIONAL GEOGRAPHIC SOCIETY, WASHINGTON, D. C. An Association Organized for "The Increase and Diffusion of Geographic Knowledge." Howell's Systematic Collections of Fine Minerals and Rocks Our Washington School Collections are now in daily use in many homes as well as schools and colleges throughout the country. The study of MINERALOGY will become extremely fasci nating when you have authentic specimens at hand. Members of the U. S. Geological Survey and National Museum have aided in the preparation of these collections, careful attention having been given in their selection in order that they might, in a general way, cover the field of Mineralogy. Collection No. 1 contains 20 Rocks and 20 Minerals. Collection No. 2 contains 40 Minerals. Collection No. 3 contains 40 Rocks. We will send with each of these collections one extra set of Duplicate Fragments, unlabeled; also a descriptive 63-page text book. The unlabeled specimens are used in comparing with the larger labeled specimens, and it will be readily seen how this comparison serves to impress on the mind and make one familiar with the distinctive characters of each rock and mineral. The texts for these collections have been prepared by Mr. J . S. Diller, Geologist with the United States Geo logical Survey. Each specimen is labeled and the corre sponding number and name of specimen will be found on the cover of the case. There is also a description in the text book pointing out the distinctive characteristics of each specimen and its principal uses. Each collection selected with great care, correctly labeled, and placed in a neat, substantial case, a minia ture of which is seen in the illustration, and accom panied with an extra set of Duplicate Fragments, unlabeled. Price, $2.00. When writing please be sure to mention the number of collection desired. Howell's Relief Maps and Models are the World's Standard. Send for catalogue giving full description. HOWELL'S MICROCOSM, 612 17th Street N. W., WASHINGTON, D. C. "Geographic readers may depend upon the integrity of our advertisers."