DELTA OF THE RHONE. 
161 
Dauphiny, and the primary and volcanic mountains 
of Central France. 
Some of the proofs of the rapid advance of the 
land at the mouth of this river are the following : 
Strabo's description of the delta is so inapplicable 
to its present configuration as to attest a complete 
alteration in the physical features of the country 
since the Augustan age. 
A portion of land, called Mese, and described by 
Pomponius Mela as being nearly an island, is now 
far inland. Notre Dame des Ports was a harbour 
in 898, but is now a league from the shore. Psal-i 
modi was an island in 815, but is now a league frorq 
the sea. Several old lines of towers and seamark^ 
occur at different distances from the present coast^ 
all indicating the successive retreat of the sea, foxi 
each line has in its turn become useless to mari-| 
ners ; and so rapid is this retreat in some places^ 
that the tower of Tignaux, erected on the shore a^ 
late as the year 1737, is now a French mile remote 
from it. The sea opposite the mouth of the Rhonq 
deepens gradually from four to forty fathoms withi 
in a distance of six or seven miles, over which th^ 
discoloured water extends.* j 
It has been satisfactorily ascertained, that a greaf 
proportion, at least, of the earthy deposite at thd 
mouth of the Rhone becomes changed into solid 
rock. I 
In the museum of Montpellier is a cannon takei^ 
up from the sea near the mouth of the river, imbed^ 
ded in a crystalline calcareous rock. Large massJ 
es, also, are continually taken up of an arenaceous 
rock, cemented by calcareous matter, including 
multitudes of broken shells of recent species. Mr, 
Lyell states, That the observations lately made 
on this subject corroborate the former statement of 
Marsilli, that the earthy deposites of the coast of 
Languedoc form a stony substance, for which rea- 
* Lyell, from Bouche, Chorographie, &c. 
02 
