THE ABABS. 595 



between Tadmor and Rakka, by observers whose names have 

 been transmitted to us by Ebn-Junis, has proved less im- 

 portant in its results than by the evidence which it affords of 

 the scientific culture of the Arabian race. 



We must regard among the results yielded by the reflection 

 of this culture, in the west, the astronomical congress held 

 at Toledo, in Christian Spain, under Alfonso of Castille, in 

 which the Rabbin Isaac Ebn Sid Hazan played an important 

 part ; and in the far east, the observatory founded by Ilschan 

 Holagu, the grandson of the great conqueror Kenghis Khan, 

 on a hill near Meraghar, and supplied with many instruments. 

 It was here that Nassir Eddin of Tus, in Khorasan, made his 

 observations. These individual facts deserve to be noticed in 

 a history of the contemplation of the universe, since they tend 

 vividly to remind us of how much the Arabs have effected 

 in diffusing knowledge over vast tracts of territory and in 

 accumulating those numerical data which contributed in a 

 great degree during the important period of Kepler and 

 Tycho, to lay the foundation of theoretical astronomy, and of 

 correct views of the movements of the heavenly bodies. The 

 spark kindled in those parts of Asia which were peopled by 

 Tartars spread, in the fifteenth century, westward to Samar- 

 cand, where Ulugh Beig, of the race of Timour, esta- 

 blished, besides an observatory, a gymnasium after the 

 manner of the Alexandrian Museum, and caused a catalogue 

 of stars to be drawn up, which was based on wholly new and 

 independent observations.* 



Besides making laudatory mention of that which we owe 

 to the natural science of the Arabs in both the terrestrial 

 and celestial spheres, we must likewise allude to their con- 

 tributions in separate paths of intellectual development to the 

 general mass of mathematical science. According to the most 

 recent works which have appeared in England, France, and 

 Germany f on the history of mathematics, we learn that "the 



* On the observatory of Meragha, see Delambre, Histoire de V Astro- 

 nomie du Moyen Age, pp. 198-203 ; and Am. Sedillot, Mem, sur lea 

 Instrumens Arabes, 1841, pp. 201-205, where the gnomon is described 

 with a circular opening. On the peculiarities of the star catalogue of 

 Ulugh Beig, see J. J. Se"dillot, Traite des Instrumens Astronomiques 

 des Arabes, 1834, p. 4. 



f Colebrooke, Algebra with Arithmetic and Mensuration, from the 

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