INDEX. 



007 



Tackle, PI. 4, 17- 



Tails of comets, 407, PI. 33. 



Tambourine, 313. 



Tangent, PL 1. 



Tangents, 82. 



Tarquin, 181. 



Tartalea, 189; d. 1557- 



Tartini, 317. 



Taurus, 401. 



Taylor, 317, 379, 589. 



Teeth of wheels, 135, PL 15. 



Telegraph, 76, PL 6. 



Telescope, 375. 



Telescopes, 334- -338, PL 28. 



Temper, 110. 



Temperament, 309, PI. 25. 



Temperate zones, 436. 



Temperature, 544. 



Temperature of running water, 227. 



Tempering of metals, 494. 



Temper of iron, 480. 



Tenacity, 482. 



Tenerifle, 547. 



Tenon, 129. 



Tertiary mountains, 439. 



Terpander, 315. 



Terrella, or magnet in a globe, 535. 



Terrestrial magnetism, 534. 



Terrestrial refraction, 346. 



Teylerian machine, 525. 



Thales, 181, 182,453, 581 ; b. 636, d. 546, B.C. 



Thames tunnel, 271. 



Thawing, 546. 



Theodolite, 80. 



Theon, 463. 



Theophrastus, 582; b. 373, d. 288, B.C. 



Theories of light, 359. 



Theory of electricity, 507- 



Theory of optics, 320. 



Thermometers, 497. 544, 584. 



Thermomultiplier, 504. 



Thermoscope, PL 39. 



Theuth, 181. 



Thick plates, 369, PL 30. 



Thin plates, 368, PL 30. 



Thoth, 181. 



Threshing machines, 178. 



Threshing mill, PI. 18. 



Throwing a stone, 173. 



Throwing wheels, 250, PL 22. 



Thunder, 557. 



Thunderstorm, 558, 559. 



Thyreoid cartilage, 312. 



Tibiae, 315. 



Tide machine, 258. 



Tides, 441, PL 38. 



Tides of the Atlantic, 444. 



Tie beam, 130. 



Time, 16, 144, 426. 



Timekeepers, 144, 461. 



Timocharis, 402, 454. 



Tint, PL 6. 



Ton, 95. 



Topham, 99. 



Torpedo, 523. 



Torre del Greco, 562. 



Torricelli, 207, 277, 584 ; b. 1608, d. 1647- 



Torricellian vacuum, 260, 2/7. 



Torrid zone, 436. 



Torsion, 105, 108. 



Total reflection, 324, 362. 



Tottering equilibrium, PL 3. 



Toughness, 110, 482. 



Tourmalin, 371, 372, 520. 



Tournefort, 685 ; b. 1656, d. 1708. 



Trachea, 312. 



Tracheae of plants, 568. 



Trade winds, 548, 585, PL 42, 43. 



Transit circle, PL 35. 



Transit instruments, 429, PL 35. 



Transverse strain, 130. 



Trevithick, 257, 267, 272. 



Triad, 307. 



Triangle, representing forces, PL 3. 



Triangular compasses, 78, PL 6. 



TrichuVus, 566. 



Triple stars, 393. 



Trithemius, 145. 



Trituration, 177. 



1, 18, PL 1. 



Trochoid, 



Trombone, 314. 



Tropical year, 427. 



Tropics, 436. 



Troughton, PL 7, 8. 



Trumpet, 314. 



Trumpet Marigni, 312, PL 25. 



Tubes, 108. 



Tun, 95. 



Tuning fork, 314, 503. 



Tuscan column, PL 12. 



Twilight, 418, 433, PL 34. 



Twinkling, 389. 



Twins, 395. 



Twisted ropes, 53. 



Twisting, 104, 108, 139. 



Tycho Brahe, 457; b. 1546, d.1601. 



Tychonic system, PL 38. 



Tympanum, 302. 



Type metal, 94. 



Ubaldi, 189. 



Ulloa, 284, 406 ; b. 1716, d. 1795. 



Ulugh Beigh, 456. 



Umbrella, 294. 



Undershot wheel, 245, PL 22. 



Undulations of light, 365. 



Undulatory theory of light, 370. 



Unequal balance, PL 8. 



Union, 480. 



Union of flexible fibres, 138. 



Union of lights, 364. 



Unit of engine power, 103. 



Uranus, 405. 



Uvea, 351. 



Valerius, 189. 



Valves, 242, PL 21. 



Valves of canals, 240. 



Vandelli, 284. 



Van Eyck. See Eyck. 



Van Marum, 525. 



Vapour, 551, 555. 



Vapours, 205, 558. 



Vapours negatively electrical, 520. 



Variation chart, 585, PL 41, 42, 43. 



Variation in London and in the West Indies 

 536. 



Variation of the compass, 536, 583, 585, PL 41. 



Variations of temperature, 544, 545. 



Varro, 75. 



Vegetable anatomy, 567- 



Vegetables, 566. 



Velocities of the planets, PL 32. 



Velocity, 22, 244. Effect of velocity in overcom- 

 ing strength, 111. 



Velocity due to a height, 25. 



Velocity of a blast, 263. 



Velocity of an impulse, 111. 



Velocity of descent, 33. 



Velocity of electricity, 516. 



Velocity of fluids, 211. 



Velocity of friction, 486- 



Velocity of sound, 289, 291, 292. 



Velocity of light, 341. 



Vena contracta, PI. 20.. 



Ventilation, 264. 



Venturi, 213,225, 226, 251, PI. 20. 



Venus, 403, 418, 419, 422, 431, PL 33. 



Vera, PL 22. 



Vermes, 576. 



Vernier, 81, PL 7. 



Vertical pipe, 216, PL 20. 



Vessel, 248. 



Vessels of plants, 568. 



Vesta, 400, 404. 



Vestibule, 302. 



Vesuvius, 562. 



Vibrating cord, PL 25. 



Vibrations, 295, 305, PL 25. 



Vibrations of cords, 297. 



Vibrations of fluids, 217. 



Vibrations of heat, 502. 



Vibrations of sounding bodies, 147. 



Vices, 170. 



Vielle, 312. 



Vince, 50, 117, 382. 



