r 



ANALYTICAL INDEX. 



Gauge to ascertain the level of water in 

 steam-boilers, ii. 502. 



Geographical surface of the planets, i. 61. 



Gilbert's discoveries in electricity, i. 104. 



Glass, the cheapest, but not the best mate- 

 rial for mirrors, i. 265. 



Globules of the blood, ii. 25. 



Governor, the, ii. 463. 



Grate and ash-pit for steam-boiler, construc- 

 tion of, ii. 499. 



Gravity, centre of, ii. 221-240. 



Great Bear, ii. 333. 



Great comet seen in 1456, i. 178. 



Great frost in London, i. 166. 



Great power of steam, ii. 401. 



Green sea, the cause of, i. 194. 



Grey's discoveries in electricity, i. 105. 



Grey and Wheeler's experiments in elec- 

 tricity, i. 106. 



Grotthus's hypothesis of galvanism, i. 378. 



Groups of the planets, inner and outer, i. 

 56. 



H. 



Hadley's sextant, i. 566. 



Halley's comet, i. 171-190; his description 

 of a total eclipse of the sun, i. 83 ; his re- 

 searches on the subject of comets, i. 180. 



Harding discovers Juno, i. 206. 



Harris's explanation of ba-11-lightning, i. 541 ; 

 his lightning-conductors for ships, ii. 104. 



Hawksbee's experiments in electricity, i. 105. 

 Heat, i. 325-334 ; radiation of, i. 437-456 ; 



heat evolved by compressed air, ii. 33 ; in 



the process of combustion, ii. 495 ; con- 

 duction of, ii. 179-184. 

 Heat of artificial light, ii. 193. 

 Heat and light, relation of, ii. 187-194. 

 Heat lightning, i. 545. 

 Heavens, how to observe the, ii. 331-353; 



Herschel's analysis of, ii. 378. 

 Hecla, experiment with the, ii. 565. 

 Heights, measurement of, i. 297. 

 Hemispheres, northern and southern, i. 562. 

 Hemp-packed piston, ii. 484. 

 Herschel, or Uranus, its diameter, bulk, and 



distance from the sun, i. 253. 

 Herschel's observations of the planet Mars, 



i. 152 ; his observations on Sirius, ii. 338 ; 



his catalogue of nebulae, ii. 392. 

 Hish mountains on the planets Mercury and 



Venus, i. 148. 



) Hook's theory of combustion, ii. 327. 

 Horse-power of steam-engines, ii. 516. 

 How comets may be recognised, i. 173. 

 Howard's improvement in the process of 



sugar-refining, ii. 170. 

 How to observe the heavens, ii. 331-353. 

 Human body, temperature of the, ii. 88. 

 Hull's patent for towing ships against wind | 



and tide, ii. 443. 



Humboldt's observations of land-spout in 



the Steppes of South America, i. 600. 

 Hunter's screw, ii. 291, 292. 

 Hunting-cog, ii. 264. 

 Hydrogen gas in coal, ii. 494. 

 Hygrometers, ii. 168. 



Identity of lightning and electricity, i. 119, 



549. 



Illusion of the air-drawn dagger, i. 264. 

 Image of an object in a plane reflector, i. 



262 ; image of the banks of a lake or river, 



i. 265. 



Impediments to motion, ii. 34. 

 Impenetrability, ii. 21 ; of air, i. 196. 

 Incandescence, ii. 188. 

 Inclined plane, wedge and screw, the, ii. 



283-294. 



Jmcompressibility of liquids, ii. 32. 

 Indicator invented by Watt, ii. 508. 

 Induction discovered by Franklin, i. 131; 



induction between the clouds and the 



earth, ii. 72. 



Inductive action of lightning, ii. 71. 

 Inequalities of day and night, i. 485. 

 Inertia (vide Action and Reaction), ii. 197 ; 



in a single body, ii. 198; consequence of 



in two or more bodies, ii. 199. 

 Ink-bottles, i. 301. 

 Ink-bottle, pneumatic, ii. 174. 

 Inundations from subterranean sources, ii. 77. 

 Invention of the Leyden vial, i. 110; of 



lightning conductors, i. 125. 

 Invisible rays of heat, i. 439. 

 Isolated clouds discharge lightning, i. 534. 



J. 



Juno discovered by Dr. Harding, i. 206. 

 Jupiter, i. 237-244 ; diurnal rotation of, i. 



238; belts and telescopic appearance of, 



i. 239 ; appearance of the sun at, i. 242; 



his satellites, i. 243 ; the variety of his 



months, i. 244. 



K. 



Kepler show a correspondence between the 



tides and the phases of the moon, i. 211. 

 Knee-joint, effect of the, ii. 234. 



L. 



La Couronne des Tasses, i. 367. 



Lalande, i. 183. 



Land-spout at Montpellier, France, i. 599 ; 



atf Escalades, i. 600; at Marchefroid, i. 



601; Ossonval, i. 601. 

 Laplace's experiments in electricity, i. 139 ; 



his nebular hypothesis, ii. 395. 

 Lardner's experiments on the Great Western 



railway in England, ii. 562. 

 Latent heat, i. 331 ; of steam, ii. 300. 

 Lateral or divided discharges of lightning, 



ii. 107. 



