Africa, children's hand-work, illustrating home life of the natives, including the elephants and the lions, 168 Agassiz, Louis, and his stone hut, 43; adventure in the crevasse, 51; on the height of ancient glaciers, 123 Air, origin of, 16; how corals get their breath, 225 Alaska, the flowers and the snow line, 44 Albany, Atlantic tides at, 221 Alleghany Mountains, birth of, 10 Alps, mountain pastures, 41; how rain drops helped carve the Alps, 67; why the Alps don't run north and south, 136; glacial "autographs" on their walls, 255 Amazon River, its stately flow, 74 Ants, how they help teach men how volcanoes are built, 123 Apollo, how he lighted the world, 2 Appalachian Mountains, birth of, 10 Arabian desert, physiognomy and complexion, 165 Arabian Sea, why its waves salute the Himalayas, 140 Arabs, life in the desert, 183; and the Simoom, 184 Atlas Mountains, morning beauty of, 163 Atoms, defined, relation to molecules, 110 Aurora, the dawn goddess and her chariot, 2 Avalanches, impulsiveness of; snap-shot at one in motion, 63 Bad Lands, why so called, 114 Bar Harbor, Nature's remarkable masonry in Castle Rock, 228 Bald Mountains, how they got their crowns shaved off, 26, 28, 123 Beavers, as lake makers, 192 Bedding planes, defined, 217 Bees, and Alpine flowers, 45; why they hide from the cloud shadows, 56; shape of honey cells and basaltic columns, 243 Beetles, varieties in desert places, 180; use of poison gas, 182 Big Round Top Mountain, how it lost its peak, 248 Birds, life in the desert, 178 Bombs (volcanic), what they are and how they are made, 129 Boulders, Agassiz' monument, 54; travels of Plymouth Rock, 64; boulders on a New England hill, 145; why the Indians worshipped a boulder, 146; the strange stranger on Mount Abu, 147; as mountain climbers, 147, 152; why there are no big caves in boulder regions, 148; how boulders help tell the secret of the Ice Age, 149; how torrents help shape, 151; how glaciers carry, 151; how boulders ride on the water, 153; how Jack Frost builds boulder walls, 154; how the sun helps shape boulders, 155; Geikie on the story told by a conglomerate boulder, 155; Ruskin on boulders in art, 157; why boulders sometimes jump up from the ground, 158; how rain drops split boulders, 171; how boulders shiver their skins off, 170; boulders in the rock mills of the sea, 216; how perched boulders are perched, 149; the perched boulder in Bronx Park, in New York City, and its autograph, 250 Bridal Veil Falls, how it got its name and why it hurries to "catch the train," 74 Butterflies, how they help in Alpine flower gardening, 46; why they hide from the cloud shadows, 56 Cactus, the desert water bottle, 174 Cactus wren, how she bars her front door against her bad neighbors, 177