_Field Geology._ 4th Edition, by F. H. Lahee, 1941, McGraw-Hill Book Co. Recognition and interpretation of geologic structures and topographic forms as they are observed, and methods of geologic work. PRECIOUS STONES _A Book of Precious Stones._ By J. Wodiska, 1910, G. P. Putnam’s Sons. Written for jewelers, but of general interest. _The Curious Lore of Precious Stones._ By G. F. Kunz, 1913, Lippincott. Legends and stories of the gem minerals. _The Magic of Jewels and Charms._ By G. F. Kunz, 1915, Lippincott. _Popular Gemology._ By R. M. Pearl, 1948, John Wiley and Sons. Scientific and industrial uses of gems, current information about their locality and production. FOSSILS _An Introduction to the Study of Fossils._ By H. W. Shimer, 1933, Macmillan Co. An introductory textbook about fossil plants and animals. _Invertebrate Paleontology._ By W. H. Twenhofel and R. P. Shrock, 1935, McGraw-Hill Book Co. _Textbook of Geology Part II—Historical Geology._ 4th Edition, by C. Schuchert and C. O. Dunbar, 1941, John Wiley and Sons. The story of the development of life through the ages. INDEX A Actinolite, 120 Adobe, 210 Agate, 107 Agate, moss, 73, 108 Alabaster, 152 Albertite, 229 Albite, 110, 113, 115 Almandine, 97 Almandite, 122, 123 Aluminum bronze, 74 Aluminum group, 73 Amazon stone, 114 Amber, 223 Amethyst, 104 Amethyst, Oriental, 75 Amianthus, 120 Amphibole group, 119 Amygdoloid, 194 Amygdoloidal, 176 Analcite, 141 Andesite, 113, 187 Andradite, 122, 124 Anglesite, 62 Anhydrite, 149 Anorthite, 110, 113 Anorthosite, 183 Anthracite, 218, 222 Antimony, 81 Antimony, gray, 81 Apatite, 160 Aquamarine, 125 Aragonite, 147 Argentite, 35 Argillite, 242 Arkose, 206 Arsenic group, 78 Arsenopyrite, 79 Asbestos, 120, 140 Augite, 118 Aventurine, 104 Azurite, 46 B Barite, 154 Barium group, 154 Basalt, 188 Batholith, 174 Bauxite, 77 Beryl, 125 Beryl, golden, 125 Beryllium, 125 Bibliography, 270 Biotite, 129, 130 Bitumen, 228 Black jack, 65 Bloodstone, 106 Bog lime, 213 Bombs, 191 Boracite, 164 Borax, 165 Bornite, 41 Brass, 64 Breccia, 191, 198 Brittania metal, 81 Bronze, 38 Bronze Age, 38 Bronzite, 118 Bytownite, 113