466 



IXDEX. 



THOMPSON 



Thompson, Benjamin (see Rumford) 



Thomson, Dr., on Dalton's theory, 377 ; 

 Sir W. cited, 323, 434 



Thoracic duct, Pecquet on the use of, 114 



Tides, Newton on cause of, 155 



Torricelli on weight of atmosphere, 117 ; 

 invents barometer, 118 



Torricellian vacuum, 119 



Toumefort's classification of plants, 145 



Tower, Hunter dissects the wild beasts of 

 the, 198 



Transits of Mercury and Venus,- 156-63 ; 

 Halley's method of measuring, 160 ; De- 

 lisle 's method of measuring, 266 ; dia- 

 grams of, 160-61 ; expeditions, 162 



Transparency of glass, cause of, 177 



Trianon, Jardin de, 208 



Truth, our want of faith in the power of, 

 436 



Tycho Brahe, his life and astronomical 

 work, 78 ; Galileo and Kepler compared, 

 1 02 



Tychonic system, 78 



Tylor, E. B., illustrations of refraction of 

 light, 178 



Tyndall, Dr., on heat, 340 



T TNDULATORY theory of light, 175, 

 ^-^ 303 ; explains interference, 305 

 Uniform action of geological change, 409 

 Upsala, Linnaeus's botanical garden at, 



208 



TJranienburg, Tycho's observatory at, 79 

 Uranus, discovery of, 272 ; its irregular 



movements lead to discovery of Neptune, 



292-294 



T7ACUUM, Torricellian, 119 



Valleys, excavation of, n 

 Valves in veins discovered by Fabricius, 



in ; use of, 112 

 Van Helmont, chemistry of, 72 

 Varieties, useful ones alone survive, 430 

 Vasco de Gama sees southern stars, 57 

 Vegetable anatomy, 140 

 Veins, Galen on, 34 ; action of discovered 



by Harvey, in; valves in, discovered 



by Fabricius, in 

 Velocity of light measured, 172 

 Venus, phases of, agree with Copernican 



theory, 91 

 Venus, transits of, 147 ; used to measure 



sun's distance, 158 ; Halley's method of 



measuring, 160 ; diagrams illustrating, 



WILLIAM 



159, 160, 161 ; Delisle's method of 



measuring, 266 



Vertebrata, term explained, 396 

 Vesalius, his work in anatomy, 67 ; ban- 

 ishment and death of, 68 

 Vessels and fibres of plants, 140 

 Vesta discovered, 290 

 Vibrations, light a series of, 176 ; of light 



complex, 313 



Vinci, Leonardo da, inventions of, 58 

 Vital fluids, belief of alchemists in, 192 ; 



spirits, belief in, no 

 Vitellio on refraction, 106 

 Viviparous and oviparous animals, 143 

 Volcanoes, Pythagoras on, 12 ; mass of 



lava thrown out from, 408 

 Voltaic electricity, 261 ; pile, 263 

 Volta on electricity, 261 ; his crown of 



cups, 262 ; his controversy with Galvani, 



260 



Volume and pressure, relations of, 130 

 Von Baer on embryology, 400 

 Voyages round the world, 56 

 Vulcan, god of volcanoes, 7 

 Vulcanists and Neptunists, 218 



WALES, moraines and erratic blocks 

 of, 44 



Wallace, Mr. A. R., figures drawn by, 97 ; 

 on natural selection, 425, 426 ; on pro- 

 lificness of birds, 429 



Wallis, Dr., his description of the Royal 

 Society, 125 



Water, composition of, 231, 239, 372 ; 

 rising in a vacuum, 117 ; latent heat of, 

 243 ; boiled by friction, 332 ; rise of 

 temperature in by friction calculated, 

 336 ; decomposed by sodium, 375 



Watt, his early life, 244 ; not the first to 

 make a steam-engine, 245 ; his separate 

 condenser, 248 ; his double-acting engine, 

 250 ; his partnership with Boulton, 251 



Wave-theory of light, 175 ; explains inter- 

 ference, 305 



Waves of light in a crystal, 313 



Wedgwood, Dr. T., on sun-pictures, 317 



Weight of bodies explained by gravitation, 

 154 ; of chemical elements, 373 



Wenzel on law of definite proportions, 373 



Werner on rocks and fossils, 217 



Westminster Abbey, Newton buried in, 

 171 



Wheatstone patents electric telegraph, 357 



William of Orange founds Leyden Univer- 

 sity, 191 



