INDEX. 



Union, I. 627, II. 377. 

 Union of flexible fibres, I. 



180, II. 181. 

 Union of lights, I. 464. 

 Unit, II. 1. 



Unit of measures, II. 146. 

 Universal measure, II. 146. 

 Unloading ships, II. 199, 



243. 

 Unlocking horses, II. 203. 

 Unrolling books, II. 159. 

 Unterbcrger, II. 113. 

 Untersucliungen vom 



nieere, II. 292. 

 Unusual refraction,II. 302. 

 Unzer, II. 474. 

 Upholstery, II. 179. 

 Upsal. Academy at Upsal, 



II. 108. 

 Uranometer, II. 353. 

 Uranus, I. 509. 

 Ursprung der gebirge, II. 



496. 

 Uvea, I. 447, II. 82, 311, 



530. 

 Vacuum, II. 377, 396, 420, 



423. 

 Valenciennes, II. 157. 

 Valentin, II. 326. 

 Valerius, I. 247, 253. 

 Vallanccy, 11. 234. 

 Vallemont, II. 440. 

 Vallies, II. 498. 

 Vallisneri, II. 480. 

 Valsalva, II. 271. 

 Valve of a pumja, II. 252. 

 Valves, I. 317, PI. 21. II. 



246. 

 Valves of canals, I. 315. 

 Vandelli, I. 364. 

 Vanderraonde, II. 273. 

 Vanderzyl, II. 126. 

 Vanes, II. 236. 

 Van Eyck. See Eyck. 

 Vanishing point, II. 31. 

 Van Marum, I. 680, II. 



400, 416, 431. 



Van Swinden, II. 128, rar,, 

 380, 388, 394, 4^7, 1 l(j, 

 489. 

 Vapour, I. 706, 711, II. 

 396, 420, 426, 464. 



Vapour baths, II. 410. 



Vapours, I. 271, 714, II. 

 60, 252, 388, 427, 476. 



Vapours negatively electri- 

 cal, I. 674. 



Vara, II. 153, 154. 



Varenius, II. 224, 305. 



Variable pendulums, II. 

 133. 



Variable quantities, II. 7, 

 119. 



Variation, IF. 365, 440. 



Variation chart, I. PI. 41 

 . .43. 



Variation in London and in 

 the Westlndies, I. 691. 



Variation of curvature, II. 

 120. 



Variation of gravity, II. 

 359. 



Variation of the barome- 

 ter, II. 462. 



Variation of the compass, 

 I. 690, 747, 749, PI. 41. 



Variation of the declina- 

 tion, or change of varia- 

 tion, II; 691. 



Variation of the moon, II. 

 341. 



Variations, II. 66, 119. 



Variations of temperature, 

 I. 698. 



Variations of the tides, II. 

 342. 



Variations of triangles, II. 

 119. 



Varignon, 11. 129, 557, 558. 



Varnish, II. 158, 180. 



Varnish for electrical ma- 

 chines, II. 430. 



Varnish microscopes, II. 

 286. 



Varnish of silk, II. 186. 

 Varro, I 98. 

 Vaults, II. 176. 

 V^ausenville, II. 128. 

 Vega, II. 113, 117, 152, 



162, 163. 

 Vegetable anatomy, I. 726, 



II. 512. 

 Vegetable materials, II. 



184. 

 Vegetable physiplogy, II. 



512. 

 Vegetables, I. 723. 

 Vegetation, II. 323, 424, 



512. 

 Velocities, 11. 7. 

 Velocities of the planets, I. 



PI. 32. 

 Velocity, I. 29, 320, II. 29. 

 Effect of velocity in over- 

 coming strength, I. 144. 

 Velocity and force, II. 139. 

 Velocity due to a height, I. 



32. 

 Velocity of a blast, I. 344. 

 Velocity of air, II. 223. 

 Velocity of a jet, II. 60. 

 Velocity of an impulse, I, 



144. 

 Velocity of descent, I. 43. 

 Velocity of electricity, I. 



668. 

 Velocity of fluids, I. 279, 



II. 235. 

 Velocity of friction, I. 633. 

 Velocity of light, I. 436, II. 



293, 320. 

 Velocity of radiant heat, II. 



407. 

 Velocity of rivers, II. 225. 

 Velocity of ships, II. 241. 

 Velocity of sound, II. 68, 



69, 264, 537. 

 Velocity of water wheels, 



II. 237. 

 Velocity of waves, II. 64, 

 224. 



Velocity producing frac- 

 ture, II. 169. 

 Velser, II. 331. 

 Velveret, II. 187. 

 Vena contracts, I. PI. 20, 



II. 223, 535. 

 Venetian painting, II. 143. 

 Venloo, II. 264. 

 Vent^nat, II. 512. 

 Ventilation, I. 344. 

 Ventilation by heat, II. 



257. 

 Ventilators, II. 264. 

 Ventilators simply mecha- 

 nical, II. 252. 

 Ventriloquism, II. 276. 

 Ventriloquists, II. 550. 

 Venturi, I. 281, 297, 328, 

 PI. 20, II. 223, 531, 534, 

 539. 

 Venus, 1.507,527,531,538, 

 544, PI. 33, II. 310, 333, 

 340, 344, 372, 374, 378. 

 Vera, I. PI. 22. 

 Vera's rope machine, II. 



250. 

 Veratti, II. 415. 

 Verdries,II. 125. 

 Vergilius, II. 216. 

 Vermes, I. 737. 

 Vernier, I. 105, PI. 7, II. 



218. 

 Verniers, II. 352. 

 Verona, II. 110. 

 Verschock, II. 154. 

 Versed sine, II. 15. 

 Vertical gnomon, II. 348. 

 Vertical pipe, I. 285, PI. 20, 



II. 223. 

 Vesicles in the atmosphere, 



II. 306. 

 Vesicular vapour, II, 464. 

 Vessel, I. 325. 

 Vessels of plants, I. 727, 



II. 614. 

 Vessels vof the crystaliine 

 lens, II. 598. 



