LETTERS FROM 
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deucy to depress the water of the Mediter¬ 
ranean, and to force it out through the 
Straits, thereby diminishing, or for a short 
time even quite counteracting, the usual cur¬ 
rent. The same effect would be produced 
by the cessation of strong westerly gales, 
which would raise the water of the Mediter¬ 
ranean above its usual level, and if, while in 
this state of over-repletion, the wind should 
suddenly shift round to the eastward, it ap¬ 
pears quite possible that for a time the 
current through the Straits might even set to 
the westward. 
I remember we used to be taught at school, 
that the cause of this flow of water into the 
Mediterranean, was the prodigious evapora¬ 
tion which takes place from its surface, occa¬ 
sioning a loss, which even the many mighty 
rivers which empty themselves into it cannot 
supply. But I do not know whether such 
