ANALYTICAL INDEX. 



47 



W : ,t-T wheels, ii. 255. 



Watch, general view of, ii. 267. 



W.itch-sprin:r, ii. 257. 



Watson and Bevitr's experiments in elec- 

 tricity, i. 111. 



Watt's inventions and improvements iu the 

 steam-engine, ii. 423-440 ; his air-pump, 

 ii. 423 ; his experimental apparatus, ii. 

 425 j his first patent for a steam-engine, 

 ii. 428; his steam-indfcator, ii. 5^)8; his 

 counter for the steam-ensine, ii. 510. 



U'enther almanacs, i. 159-168. 



Waves of lisht, minuteness of, i. 229. 



UY'l-re, the, ii. 287. 



\\~- -<i je, screw, and inclined plane, ii. 283- 

 294. 



Weight of air, i. 94; of the earth, i. 487. 



AVi i-.jht and force, ii. 244. 



Wdls's theory of dew, i. 456. 



Westerly winds, their effects on sailing ves- 

 sels,,!". 341. 



Wht-atstone's experiments on the speed of 

 lightning, i. 541. 



Wh> (!, the, applied to the steam-engine, ii. 

 447* 



Wheel and axle, ii. 253. 



Wheel barometer, i. 292. 



Wheelwork, ii. 253. 



Wheelwork and the lever, ii. 243-268. 



WheweH's researches oa the subject of the 

 tides, i. 217. 



Whirlwinds and water-spouts, i. 599-608. 

 Whiston's co.Tiet, ami his theory, i. 428. * 

 White's pulley, ii. 276. 

 Williams's patent for a method of^consuming 



unburnt gases, ii. 499. 

 Wilson discovers the lateral shock, i. 112. 

 I Wind, action of on sails of vessels, ii. 213. 

 | Wind and water-mills, Sineaton's improve- 

 ments ot, ii. 443. 

 i Windlass, the, ii. 254. 

 j Wings of insects, ii. 24. 

 | Wollaston's cryophorus, ii. 174. 

 Wollaston's micrometric wire, ii. 23, 24; 

 his inrettifationi on the subject of the 

 comparative e brishtness nd magnitude of 

 the stars, i. 5t(3. 

 Woolf's piston, ii. 485. 

 Working-machinery of a locomotive engine, 



plan of, ii. 547. 

 Worlds, plurality of, i. 51-64. 



Y. 



louns; s discoveries in the philosophy of 

 light, i. 233. 



Z. 



Zigzag lightning, i. 538, 556. 

 j Zodiacal constellations, ii. 338. 



