218 
fbrmation considered relatively to the great events of 
nature. It is even evident that this bank was formed 
under water; and, as I do not know that there is on the 
shores of the Mediterranean an instance of so late a re- 
cession, I conclude that at the period of the formation 
of this bank, the surface of the Red Sea was more 
elevated than that of the Mediterranean, whilst at the 
present day it is of the same level, or perhaps lower. 
The long and narrow form of the Red Sea, inter- 
sected by so many banks, shoals, and islands, necessa- 
rily renders the propagation of high tides difficult, as 
the traveller Niebuhr has well observed. The almost 
continual north and north-west winds during nine 
months of the year, must contribute to the efflux of the 
waters during ebb-tide; whilst they are obstacles to the 
propagation of high tides. This .propagation becomes 
more difficult every day in consequence of the activity 
of the petrifaction, and whi^h appears to be destined to 
choke up the Red Sea by the rapid formation of new 
banks and islands; obstacles incessantly forming in ad- 
dition to those which already opposed the free circula- 
tion of the waters. Evaporation in the Red Sea ought 
to be much stronger than in the Mediterranean, on 
account of the difference of temperature and latitude; as 
also of the deserts which surround this sea on all sides, ^ 
and which drying the air, render it more apt to absorb 
vapours. On the other hand, the Red Sea may be said 
not to receive a single drop of water from the land that 
surrounds it, since there are no rivers that empty them- 
selves into it, either from the Arabian or African coasts, 
except some occasional torrents at the period of the rains. 
Accordingly, we may rest assured, that in the course 
of the year the Red Sea loses a greater quantity of water 
than that which it receives by the tides of the ocean; 
