TO GRAND CAIRO. 05 
an immense lake. A singular pheenomenon en- chap. 
II 
grossed all our attention. One of those immense 
columns of sand, mentioned by Bruce, came 
rapidly towards us, turning upon its base as 
upon a pivot : it crossed the Nile so near to us, 
that the whirlwind by which it was carried 
placed our vessel upon its beam-ends, bearing 
its large sail quite into the water, and nearly 
upsetting the boat. As we were engaged in 
righting the vessel, the column disappeared. It 
is not probable that those columns fall suddenly 
upon any particular spot, so as to be capable of 
overwhelming an army or a caravan ; but that, 
as the sand, thus driven, is gradually accumu- 
lated, it becomes gradually dispersed, and, the 
column diminishing in its progress, at length 
disappears. A great quantity of sand is no doubt 
precipitated as the eftect, which gathers it, 
becomes weaker ; but, from witnessing such 
phaenomena upon a smaller scale, it does not 
seem likely that the whole body of the sand is 
at once abandoned. 
Parties of young Arabs continually accompa- Tumbiew. 
nied our cljerm this day, running along the banks 
of the river, and tumbling, to obtain a few par^j, 
as we see children in many parts of England; 
sometimes walking upon their hands, with their 
VOL. V. r 
