Page 512 - Travels in Arabia (Vol 2)_Neat

appendix. 471
470
APPENDIX.
in Jiddah, that southerly winds prevent
ferent quarters, during nearly the January) m
same period, at abundant water which, by
cither extremity of the sea. Thus, northerly winds the escape of the super .
the same agency, is poured in from the Gulf of
may be considered to prevail throughout the year in
Aden • but that when the north-westers exercise a
the northern part; but during June, July, and August,
’ influence to force them out of the sea, and they
they blow with the greatest violence, and then extend similar
aided by the quantity lost from evaporating causes,
to, and even without the Straits ; the water is then so are
the effects are directly the reverse ; and the reefs and
low, that the reefs, which at other times are covered,
) rocks thus become laid bare*. That a considerable
appear three and four feet above the surface. In the
quantity of water which is carried through the larger
southern portion, the southerly winds blow with an
Straits might return through the smaller, and along
equal degree of regularity from November to June;
the Arabian and Abyssinian shores, is by no means
although, when at their height, from November to
January, they in a like manner blow home to Suez; and uncertain; but the extreme inequality and variation
in the set and direction of the tides, as well as rise and
the water, to an equal degree, is found to he elevated.
With a knowledge of these circumstances, I watched fall, render it difficult to arrive at any general con­
with some attention the direction and set of the current clusion. It is true, they ebb and flow with much
in the Straits, anticipating, that when it blew fresh out velocity in the small Straits; that the period of each
of the sea, the current would follow with rapidity in the was nearly the same. I have known them at a short
same direction ; that when the wind was moderate, it distance without, to the eastward, run for eight hours
would be less sensible; and that when it fell calm, and to the westward, and but two hours in a contrary
light airs came from the south, &c., that the waters, by direction. At the Brothers, I observed its rise and
a kind of reaction, would flow back to fill up the space fall to be from five to seven feet, the night tides
which had been left. To my surprise, however, I being the highest, without reference to the age of the
found they obeyed no such general law; hut during ^oon, for it differed one day with another, sometimes
my whole stay in the larger Straits, they flowed uni- two hours, and was as high at the moon's perigee as
formly in one direction out of the sea to the eastwaid. her ap°bee. Frequently, when it had ascended to
what
Their velocity at times was upwards of three miles an appeared high-water, and had
and receded to even subsided
hour. From these, and some other observations, ma e some distance, it would again, under
before and since, I am convinced, that not only some new impulse, rise and flow over the former
also the current, in the Jtea mark.
height of the water, but —the
Sea! depend on, and are owing to the same cause f; irye°£’S ’"*7% in «» height of the water
that
strength and duration of the prevailing breezes . ^ 0X1 l8lands ? The lalm e ° n°*’ aS xn °t^er parts of the world
when the water is at its highest (from Novem aPproach the surface. ® UthoPhite cease as soon as they