ASSUAN— ABU. 



375 



wood, precious drugs, and other wares brought down from Nubia and the Upper 

 Nile. The neighbouring date groves also supply abundant cargoes for the boats 

 proceeding to Cairo and the delta. 



Under its Arabic form of As-Suân, the old Egj^ptian name of Siuin has survived 

 for nearly five thousand years, and under its Greek form of Syene had already be- 

 come famous in classical times. To geologists it recalls the granite and " syenite " 

 quarries, which have been excavated to the south of the city for a space of nearly 



Fig. 112. — AsSUAN AND THE FlUST CaTATIACT BEFORE THE OPENING OF THE EaILWAY. 



Scale 1 : 250,000. 



24' 



EH,| 



24' 



52^45 



' h of" breenwi ch 



52°65 



6 MUes. 



four miles. Here is still to be seen an obelisk 120 feet long, not yet entirely 

 detached from the rock. Astronomers also are reminded by this tiame of the 

 experiments here carried out by Eratosthenes, over twenty-one centuries ago. 

 Assuming that Syene stood exactly on the line of the tropic of Cancer, which, how- 

 ever, is not strictly correct,* and finding that at Alexandria the shadow of the 

 gnomon stood at a fiftieth on the day of the summer solstice, from these data 

 Eratosthenes deduced the degree of the earth's curvature, and consequently so far 



* Latitude of Assuan, 24° 5' 23". 



