Geography, when all our geography was at the bottom of the sea, 8; how they study geography in Boston on rainy days, 68 Geysers, and the geyser basins, 165 Giant's Causeway, its architecture, 243 Gila monster, 181 Glacial Period. (See Ice Ages.) Glacial tables, how stones go walking in glacier land, 62 Glacier Mills, 55 Glaciers, how snow changes itself to ice, 26; glaciers in their "working clothes," 29; how to make glaciers and icebergs in the schoolroom, 32; how glaciers helped make the gray stone "Temple of the Winds," 33; how the glaciers of the Ice Ages made the Great Lakes, 34; songs of the glacier and how it sings, 42, 56; a day's visit with the Alpine glaciers, 49; the crevasses and the adventure of Agassiz, 51; how long it took Agassiz to determine the nature of glacial movements, 52; why the peasants think the glacier has a soul, 54; Mr. Glacier's caterpillar tractor, 62; how the glaciers start Europe's rivers in business, 73; how pebbles tell on what part of a glacier they travelled, 251 Golden Gate, entrance to San Francisco harbor, how it was made, 224 Gorges, 26, 82 Grand Canyon, 88 Granite, ancient lineage and social standing among earth's rocks, 17; the Granites and the Fairyland of Change, 94; how they crystallize their neighbors, 103; how they help make sand, 170 Gravitation, how it pulls the worlds into roundness, 5; and helps them to grow up, 8; how it helps sea waves to salute the mountains, 139; equally careful in handling big worlds and little seeds, 261; like all power it is invisible and intangible, 276 Great Basin, records of the two great lakes it used to hold, 249 Great Lakes, how they were made in the Ice Ages, 34; an Ice Age lake that was greatest of all, 193; tides in the Great Lakes and tides in a teacup, 201; how the glaciers of the Ice Age tipped the Great Lakes up, 253 Great Salt Lake, ancient weather records on its walls, 249 Greek civilization, one of the things that do not die, 270 Harbor engineering of the rivers and the sea, 221, 222 Hieroglyphics, picture language of the Egyptians and how it was read, 258 Himalaya Mountains, glacial table on, a lesson in picture-reading, 59; why some of the Himalayas are called "hills," 117 Horse, evolution of, 266 Hot Springs (cause of), 165 Hudson River, action of the tides, 221; the Palisades, 241 Hydrogen, and the making of earth's air, 16