170 COSMOS 



EXTENSION OF THE CONTEMPLATION OF THE UNIVERSE UNDER THE 

 PTOLEMIES. MUSEUM AT SERAPEUM PECULIAR CHARACTER OF 

 THE DIRECTION OF SCIENCE AT THIS PERIOD. -ENCYCLOP/EDIC 

 LEARNING. GENERALIZATION OF THE VIEWS OF NATURE RESPECT- 

 ING THE EARTH AND THE REGIONS OF SPACE. 



AFTER the dissolution of the Macedonian empire, which in- 

 cluded territories in three continents, those germs were vari- 

 ously developed which the uniting and combining system oi 

 government of the great conqueror had cast abroad in a fruit- 

 ful soil. The more the national exclusiveness of the Hellenic 

 mode of thought vanished, and the more its creative force of 

 inspiration lost in depth and intensity, the greater was the in- 

 crease in the knowledge acquired of the connection of phenom- 

 ena by a more animated and extensive intercourse with other 

 nations, as well as by a rational mode of generalizing views 

 of nature. In the Syrian kingdom, under the Attalidse of 

 Pergamus, and under the Seleucidse and the Ptolemies, learn- 

 ing was universally favored by distinguished rulers. Grecian- 

 Egypt enjoyed the advantage of political unity, as well as that 

 of a geographical position, by which the traffic of the Indian 

 Ocean was brought within a few miles of the Mediterranean 

 by the influx of the Arabian Gulf from the Straits of Bab-el- 

 Mandeb to Suez and Akaba (running in the line of interseC' 

 tion that inclines from south-southeast to north-northwest).* 



The kingdom of the Seleucidae did not enjoy the same ad 

 vantage of maritime trade as that afforded by the form and 

 configuration of the territories of the Lagides (the Ptolemies), 

 and its stability was endangered by the dissensions fomented 

 by the various nations occupying the different satrapies. The 

 traffic carried on in the Seleucidean kingdom was besides more 

 an inland one, limited to the course of rivers or to the caravan 

 routes, which defied all the natural obstacles presented by 

 snow-capped mountain chains, elevated plateaux, and extens- 

 ive deserts. The great inland caravan trade, whose most 

 valuable articles of barter were silk, passed from the interior 

 of Asia, from the elevated plains of the Seres, north of Uttara 

 Kuril, by the stony towert (probably a fortified caravansery), 

 south of the sources of the Jaxartes, through the Valley of the 

 Oxus to the Caspian and Black Seas. On the other hand, 

 the principal traffic of the Ptolemaic empire was, in the strict- 



* See ante, p. 123. 



t Compare my geographical researches, iu Asie C entrale, t. i., p. 145 

 and 151-157 ; t. ii., p. 179. 



