144 
DESCRIPTIONS OF EGYPT. 
opinion, that it has rather encroached upon the 
land in that quarter than deserted it. Misled by 
the opinion, that Mount Casius and Heroopolis, 
a city near the bottom of the gulf, lay under the 
same meridian, though there be almost a degree 
of longitude between them, Herodotus and Pto- 
lemy have extended the distance between Mount 
Casius and the head of the Arabian gulf to 
eighty-three instead of sixty-four G. miles. From 
the respective latitudes of Suez and Farama, the 
ancient Peiusium, the nearest distance between 
the Red Sea and the Mediterranean appears to 
be about forty-eight G. miles. The intermedin 
ate space is a level plain, covered with shifting 
sand, which the eye traverses without interrup- 
tion from sea to sea. The advantages which 
this situation presented for commercial pursuits 
did not escape the observation of the ancients^ 
and, at a very early period, a canal was con-* 
structed, which connected the Red Sea with the 
Mediterranean. As the loose and sandy soil 
of the isthmus rendered it impracticable to form 
a permanent canal across its narrowest part on 
the western side, they availed themselves of the 
navigable channel of the Pelusiac branch of the 
Kile, which they ascended towards the head of 
the Delta. On the eastern side, a canal was 
conducted from the gulf of Suez to the Pelusiac 
cliannelj from which it derived a stream of water. 
