the rivers and the rock mills of the sea, 227; the river's trade-mark on its pebbles, 250 Rocky Mountains, how they were born, 10; their relation to the Mediterranean Sea that is no more, 135; why they are now so far from the sea, 138; how the mountain waves of stone resemble the waves of the sea, 140; folded strata that illustrate Ruskin's line about the strange quivering recorded in mountain rocks, 142 Romans, some of the big things we owe to them, 270 Rose of Jericho, what it is like and how it puts to sea, 176 Round Tops (Mt.), how they are formed, 123 Ruskin, on the response of rivers to the call of the sea, 76; on the sleep of lakes, 80; on mountain drawing, 140; on the strange "quivering of substance" of mountains, 141; on the art lessons to be learned from stones, 158; on the correct drawing of boulders, 160 Sahara Desert. (See Desert.) St. Lawrence River, how the Old Men of the Mountain took some of its rivers away, 30; how the Old Men used it in making the Great Lakes, 34 Salt, how Mother Nature uses it in warming over rocks, 99; how Father Neptune uses it in his rock mills, 217 Sand, how it helped build the stone "Temple of the Winds," 33; how Mother Nature dissolves it out of sandstone in her rock cookery, 99; how the crystal fairies give sand grains a new lease of life, 108; how the sand helped shape the old Indian of Mt. Abu, 147; color of desert sand, 165; how the desert makes its sand, 168; "sand roses," 168 Sandstone, its place in the rock-milling system of the sea, 227 San Francisco Bay, how it was made, the two rivers that opened its Golden Gate, 222 Saturn (planet), 5, 6