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]