460 



L\DEX. 



IRON 



Iron tools of lake-dwellings, 417 

 Islands, formation of, 12 

 Isothermal lines, Humboldt on, 385 

 Italy, early scientific societies in, 126 



JAMES, Sir H., on weight of the earth, 

 280 



Jansen makes a telescope, 87 

 Jews, medical knowledge of the, 39 

 Joule, Dr., experiments on the mechanical 



equivalent of heat, 335-338 

 Juno discovered, 290 

 Jupiter, atmosphere of, 327 ; his moons, 



90 ; velocity of light measured by, 172 ; 



and Saturn, long inequality of, 269 

 Jura mountains, erratics of the, 413 

 Jussieu's natural system of plants, 211, 



382 



"TRENT'S Hole, flint implements in, 



-tV 416 



Kepler, life and difficulties of, 95, 101 ; on 

 structure of eye, 96 ; his telescope, 97 ; 

 his first law, 97 ; second law, 99 ; third 

 law, 100 ; his delight at Galileo's dis- 

 coveries, 100 ; on refraction, 100 ; pre- 

 dicted transits of Mercury and Venus, 

 157 ; finished Rudolphine tables, 101 ; 

 compared with Tycho and Galileo, 102 



Kew gardens, 208 



Kircher invents magic lantern, 76 



Kirchhoff on dark lines in solar spectrum, 

 323 ; his spectroscope, 324 



Kite, Franklin's, 257 



Koran forbade dissection, 40 



LACTEALS discovered by Asellius, 

 114 

 Lagrange, 266 : on libration of the moon, 



267 ; on stability of planetary orbits, 



270 

 Lake-dwellings of Switzerland, 416 ; tools 



and food found in, 417 

 Lamarck, history of, 389 ; on invertebrates, 



391 ; on development of animals, 391 ; 



his 'Philosophic Zoologique,' 393 ; weak 



point in his theory, 393 

 Lamont on variations of magnetic needle, 



355 



Land, conversion of, into sea, ir 

 Laplace, 267 ; on long inequality of Jupiter 



and Saturn, 269 ; on moon's acceleration, 



270 ; on heat, 336 



LINN^US 



Lassell on Neptune's moon, 295 



Latent heat, Black on, 241 ; of water, 243 ; 

 theory of, applied by Watt, 244, 248 ; 

 explained, 334 



Latitude, first parallel of, laid down, 27 



Laughing-gas, Davy's experiments with, 

 363 _ 



Lavoisier the founder of modern chemistry, 

 235 ; his experiments, 237 ; his death, 239 



Law of compressibility of gases, 128 ; of 

 definite proportions in chemistry, 372 , 

 of multiple proportions, 373 ; of gravita- 

 tion, 151 ; of refraction discovered by 

 Snellius, 107 



Laws of Kepler, 97, 99, 100 



Leaves of plants, Bonnet on use of, 200 



Leeuwenhoeck on animalcules, 139 



Leibnitz on differential calculus, 148 



Lenses, magnifying power of convex, 49 ; 

 Alhagen on use of, 48 ; Porta on, 76 ; 

 Galileo on, 88 ; Kepler on, 96 



Leslie, Sir J., on refraction of heat, 340 



Lever, Archimedes on the, 22 



Leverrier calculates the position of Nep- 

 tune, 292, 294 ; on November meteors, 

 299 



Leyden, medical school of, 190 



Libration of the moon, 267 



Liebig on organic chemistry, 377 



Light, Euclid on rays of, 21 ; a vibration, 

 176 ; causing colour, 177 ; polarization 

 of, 181, 309 ; compared to sound, 176, 

 178 ; dispersion of, 164, 167 ; blending 

 of colours into white, 168 ; interference 

 of, 302-306 ; bands of, in shadows, 304 ; 

 undulations compared to waves of a 

 pond, 306 ; reflection of from a soap- 

 bubble, 308 : complex vibrations of, 312 ; 

 passage of through a crystal, 313 ; 

 Roemer measures velocity of, 172 ; 

 theories of, 174, 303 ; undulatory theory 

 explained, 174-179 



Lightning, electric nature of proved by 

 Franklin, 256 ; conductors, 258 



Lilienthal, meeting of astronomers at, 289 



Limestone, fixed air obtained from, 226 ; 

 beds of Sicily, thickness of, 407 



Lines in the spectrum, 318, 320 ; their 

 cause explained, 323 



Linnsean system, 210 ; collection brought 

 to England, 212 



Linnaeus, early life of, 205, 207 ; and BufTon 

 compared, 207 ; his ' Excursions,' 208 ; 

 gives specific names to plants and 

 animals, 208 ; creates an accurate nomen- 

 clature, 211 ; modifies Ray's system, 



