Part 38

Sunrise, 234.

Sunset, 181, 182. (See Twilight.)

Suns: millions, 224; dwindling, 227; periods, 241.

Sun-spots, 1–34 passim; ancient, 8; early observations, 8; changing, 9; great, 10, 20, 24; individuality, darker, 11; leaves (q. v.), 11, 12; how observed, 18, 19; typical, 21, 22; relative size, 20; hook-shaped (see Plume), 24; signs of chaos, 27; double, 32; weather, 76, 90; periodicity, 76–78; temperature, 83; records, 85; variations, 87; (1870), 9, 15, 16, 20; (1873), 20–24; (1875), 25, 28, 30; (1876), 30, 32; (1882), 80, 83–86, 90.

Superga, 38.

Swift, Dean, 73, 131, 132. (See Gulliver.)

Sword Meteor (q. v.), 175.

Tacchini’s Investigations, 43, 49, 62, 66, 68.

Tail, 215, 216. (See Comets.)

Tan, 71.

Taylor, Bayard, 139.

Telephone, 84, 89.

Telescopes: many, 17; best, 134; alone, 227, 230; use, 233, 234.

Temperature, 101, 102, 108; of space, 224, 227.

Terminator, 147.

Thermometer, 71, 93, 102; low, 160, 163.

Time, small divisions, 241.

Tippoo Saib, 221.

Total Eclipse (q. v.), 39–48 passim, 55, 59.

Trees, lacking, 168.

Tribune, The New York, 84.

Trinity Church, 72.

Trocadéro, 112.

Trouvelot, E. L., 119, 123, 225.

Turin, 38.

Twilight, small, 38.

Tycho, 144, 229. (See Star.)

Tyndall, 98.