Geology of Mount Sinai and adjacent Countries. 195 
Second Series, Part 2, of those Transactions; and I have 
coloured it geologically, chiefly after Russegger’s beautiful 
maps of Egypt and the Sinaic Peninsula, lately published at 
Vienna; but the latter I have corrected in some places, so 
as to agree with the descriptions of Burckhardt or other 
travellers who have personally visited them. 
First, The small and poor town of Suez, called Seis by 
the Arabs,—meaning a “ little mouth,”—now a place of such 
constant communication by the English, since the late esta- 
blishment of steam navigation to and from India, is situated 
on a low neck of land, but little raised above the level of the 
high water of the gulf. The land there consists of gravel 
and sand placed upon rocks of a very recent marine forma- 
tion ; it is quite barren, having neither vegetation nor good 
water. The view of the opposite coast-line of the Peninsula, 
extending far southwards, with the more lofty mountain- 
summits rising behind it, is extremely fine. Near the town 
there is a ford upon a long narrow sandbank, which stretches 
across tothe eastern shore, the water at low tide not exceed- 
ing five English feet in depth. Whilst the tide at Suez, and 
on the shoals to the north, is said to rise about seven feet. 
The plain behind the town is a hard diluvial gravel ; proceed- 
ing northwards, a little short of the line of 30° north lati- 
tude, some heaps of rubbish or mounds point out the sup- 
posed site of the ancient town of Clysma, derived, I suppose, 
from KAvoua, which means “ anestuary.” Colsum or Kolzum, 
corrupted from that word, is still in use with the Arabs, who 
now call the Gulf of Suez Bahr-el-Kolzum, that is, “ the Sea 
of Kolzum.”’ 
Around the head of the gulf are extensive shoals, ap- 
parently of sand, mingled, according to some, with coral ; 
these are left bare at low tide. There exists evidence of a 
gradual filling up of the north part of the gulf, probably by 
the drifting in of sand from the north of the desert. This 
sand, brought by the north-east winds which often blow, is 
carried into the sea, and the process of filling up is still 
going on. The sea once extended much further north, and 
perhaps to the north-east. The ground at the north end is 
often covered by the sea in winter when south winds prevail, 
