Pelusium
(
Πηλούσιον, Old Test. Sin; both names are derived from
nouns meaning “mud”). A celebrated city of Lower Egypt, standing on the
east side of the easternmost mouth of the Nile, which was called after it the Pelusiac mouth,
twenty stadia (about two miles) from the sea, in the midst of morasses, from which it obtained
its name. As the key to Egypt on the northeast, and the frontier city towards Syria and
Arabia, it was strongly fortified, and was the scene of many battles and sieges. It was the
birthplace of the geographer Ptolemaeus.