L 9 I 



Humboldt, Wilhelm von, comparison 

 of the works of Lucretius, with an 

 Indian epic, 383; the sky in the 

 landscape compared in its effect to 

 the charm of the chorus in the Greek 

 tragedy, 459 ; irresistible charm of 

 mathematical studies, 737. 



Huygens, first explained the phenom- 

 ena of Saturn's ring, 706, 712; on 

 the nebulae in the sword of Orion, 

 713; his researches on light, 715 

 717. 



Hygrometers, invention of, 725. 



Hyksos, the, their Semitic origin and 

 migration, 576, 577. 



Hyperboreans, the, meteorological 

 myth of, 510, 511. 



Ibn-Baithar, Arabian botanist, 587. 



Iceland, its discovery and colonization 

 by the Northmen, 603, 604; its early 

 free constitution and literature, 610. 



Ilschan Holagu, observatory founded 

 by, 595. 



Incense of Arabia, researches on the, 

 573, 574. 



India, expedition of Alexander to, and 

 its important results on physical and 

 geographical science, 517 523. 



Indians, profound feeling of nature in 

 their most ancient poetry, 373, 460 ; 

 its influence on the imagination of the 

 East Avian nations, 397, 402 405 ; 

 its characteristics, 406 408; their 

 knowledge of landscape painting, 

 442; numerical system, 535, 597 

 698; their chemistry, 590; planetary 

 tables, 593, 594 ; algebra, 590599. 



Inductive reasoning, 546. 



Infinitesimal Calculus, results of its in- 

 vention, 737. 



Ingolf, his colonisation of Iceland, 607, 

 611. 



lonians, their mental characteristics, 

 506. 



Irish, conjectures on their early dis- 

 covery of America, 607 610. 



Isabella, Queen, letters to Columbus, 

 651, 671, 672, 



Isaiah, quotation from his prophecies, 

 575. 



Islands of the Blessed, myth of the an- 

 cients, 496. 



Italian poetry, as descriptive of nature, 

 418420' 



Ivory, commerce in, 540, 541, 



Jansen, Zacharias, optical instruments 

 invented by, 699701. 



Job, book of, its impressive descriptions 

 of the natural scenery of the East, 

 414, 415. 



John of Salisbury, 622. 



Jupiter, controversy on the disco very 

 of his satellites, and marked influence 

 of the discovery on the extension 

 of the Copernican system, 702 704. 



Kalidasa, Indian poet, 404408; his 

 Sakuntala, 404, 405, 442 ; Vikrama 

 and Urvasi, 405, 408; The Seasons, 

 405, 408, 430 ; Messenger of Clouds, 

 405, 408. 



Kepler, his eulogium on Copernicus, 

 687 ; ideas on gravitation, 691 ; 

 great discovery of the elliptic mo- 

 tion of the planets round the sun, 

 695 699 ; astronomical writings, 

 698, 699 ; on the Papal prohibition 

 of the Copernican system, 704 ; his 

 great mental and scientific charac- 

 teristics, 709, 710; on comets and 

 fixed stars, 710 712; Brewster, 

 Chasles, and Laplace, on his writings 

 and theories, 710. 



Kien-Long, Chinese Emperor, de- 

 scriptive poem bv, 463, 464. 



Kirghis Steppe, its extent and popula- 

 tion, 578. 



Klaproth, his researches on the Iiido- 

 Germanic races, 554; letter to 

 Humboldt on the invention of the 

 compass, 629. 



Klopstock, 433. 



Lagides, the. See Ptolemies. 



Lambrecht, his r Song of Alexander 

 403. 



Landscape painting. See Painting. 



Languages, their value and importance 

 in the history of the physical con- 

 templation of the universe, 470 

 473. 



Laplace, on Kepler's theory of the 

 measurement of casks, 710; on the 

 zodiacal light, 712. 



Las Casas, Bartholomew de, 637, 638, 

 679, 680. 



Lasseri, author's correspondence with 

 on the ariena of Pliny, 524; on the 



