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©cean, or by the diminution of its water, or from any 
other cause, such a coast remains uncovered and above 
the water, it must necessarily represent a confused heap of 
stones, sand, or flinty particles, improper for vegetation, 
and of course unfit for animalisation; in a word, a ground 
which is quite useless for the existence of man, and 
which, if it happen to be of any extent, acquires the de- 
nomination of a desert. 
A great part of the coasts of Morocco are in this 
state. Tangier as well as Rabat is surrounded with 
sand; Mogador, which is the most southern spot which 
I visited, is situated in the middle of a little Sahhara, in 
which the sand is forming moveable and rather high 
hills. If my supposition be founded, that these deserts be- 
came greater as we advance towards the south, we ought 
to find there the great desert Sahhara, which is only a 
repetition on a large scale of that phenomenon, which 
we see in a small one at Mogador, and in miniature at 
Rabat and Tangier. 
It is certain, that these plains of sand are depositions 
of the sea, which is sensibly withdrawing from these 
shores. The bay of Tangier is becoming choked up; 
the river at Rabat is experiencing the same effect, and is 
lessening; the same fact is visible at Mogador in the 
channel which separates it from the island, and serves it 
as a port. These facts are proved by the anchorages 
which daily become more and more confined, and very 
frequently we see whirlwinds of sand carried off by 
westerly winds from the sea- shore, and form downs or 
hills in places which never contained any, without be- 
ing counterbalanced by any opposing wind or contrary 
force sufficiently strong, so that the sand is always com- 
ing from the sea, never to return to it. Therefore, if 
vol. i. h h 
