SUN, THE: Diameter and Distance, 87. Solar observations, 88. Spots on the Sun, 88. Early observations, 88. Small telescopes and solar work, 90. Tinted glass, 91. Solar diagonal, 92. Drawing Sun-spots, 93. Ascertaining dimensions, 94. Sun-spot of June 19, 1889, 95. Eclipses of the Sun, 97. Periodicity of Spots, 100. Crateriform Structure, 101. “Willow Leaves,” 101. Rotation of the Sun, 103. Determining the Period, 104. Planetary bodies in transit, 105. Proper motion of Sun-spots, 106. Rise and decay of spots, 106. Black nuclei in the Umbræ, 106. Bright objects near Sun, 107. Cyclonic Action, 108. Sudden outbursts of Faculæ, 108. Shadows cast by Faculæ, 109. Veiled Spots, 110. Recurrent disturbances, 110. Recurrent forms, 111. Exceptional position of Spots, 111. The Solar prominences, 111. Sun-spots, 88, 347. Superstitious ideas on Comets, 227. Surface configuration of Mars, 156. —— markings on Mercury, 142. —— —— on Venus, 147. Sweeping for Comets, 249. —— for Nebulæ, 340. Swift, Discoverer of Comets, 252. ——, —— of Nebulæ, 339. Tails of Comets, 244. Tarrant on Double Stars, 291. Telescope, Invention and Development, 1. Telescopes, Cheapness and increasing number of, 57. ——, Choice of, 38. ——, Large and small, 20. ——, Mounting of, 45. ——, Testing, 43. Telescopic Comets, 256. —— Meteors, 272. —— Work, Attractions of, 85. Tempel’s Comets, 241. —— Nebula in the Pleiades, 329. —— observation of Aristarchus, 120. Temporary Stars, 312. Tenuity of Comets, 229. Terby’s White Spot on Saturn’s rings, 203. Terminator, Moon’s age and Objects near, 133. Testing Telescopes, 43. Test-objects, 55. Theophilus, 128. Thornthwaite, Method of Solar observation, 92. Tinted glass for Solar observation, 91. Titan, Transit of, 213. Total Eclipses of the Moon, 118. —— —— of the Sun, 99. Transits of Intra-Mercurial Planets, 105, 137. —— of Jupiter’s satellites and their shadows, 189, 191. —— of Mercury, 143. —— of Venus, 153. Trans-Neptunian planet, 224. Tupman, Method of tabulating Meteors, 282. ——, Remarks on a Fireball, 267. Tuttle’s Comet, 241. Twilight on Venus, 151. Twinkling of the Stars, 297. Tycho, 127. URANUS, Discovery, 215. Mistaken for a Comet, 215. True character revealed, 216. Period &c., 217. Observations, 217. His belts, 218. Further observations, 219. The satellites, 220. Ursæ Majoris ζ, 318. Ursæ Minoris α, 308. Utility of “stops,” 58. Variable Nebulæ, 327, 351. —— Stars, 309. —— ——, List of, 311. —— ——, Observations of, 321. Variations in the light of Comets, 245. Varieties of form and grouping in Nebulæ and Star-clusters, 325. —— of Meteors, 276. Vega, 301, 308. Veiled Sun-spots, 110.