SAND IN THE MEDITERRANEAN. 
455 
sand and gravel carried into tlie Mediterranean by the torrents 
of the Maritime Alps, the Ligurian Apennines, the islands of 
Corsica, Sardinia, and Sicily, and the mountans of Calabria, is 
apparently great. In mere mass, it is possible, if not probable, 
that as much rocky material, more or less comminuted, is con¬ 
tributed to the basin of the Mediterranean by Europe, even 
excluding the shores of the Adriatic and the Euxine, as is 
washed up from it upon the coasts of Africa and Syria. A 
great part of this material is thrown out again by the waves 
on the European shores of that sea. The harbors of Luni, Al- 
benga, San Kemo, and Savona west of Genoa, and of Porto 
Fino on the other side, are filling up, and the coast near Car¬ 
rara and Massa is said to have advanced upon the sea to a dis- 
any streams draining basins of no greater extent. Absolutely considered, 
then, the mass may be said to be large, but it is apparently very small as 
compared with the sand thrown up by the German Ocean and the Atlantic 
on the coasts of Denmark and of France. There are, indeed, in Arabia 
Petrsea, many torrents with very short courses, for the sea waves in many 
parts of the peninsular coast wash the base of the mountains. In these 
cases, the debris of the rocks do not reach the sea in a sufficiently com¬ 
minuted condition to be entitled to the appellation of sand, or even in the 
form of well-rounded pebbles. The fragments retain their angular shape, 
and, at some points on the coast, they become cemented together by lime 
or other binding substances held in solution or mechanical suspension in 
the sea water, and are so rapidly converted into a singularly heterogeneous 
conglomerate, that one deposit seems to be consolidated into a breccia 
before the next winter’s torrents cover it with another. 
In the northern part of the peninsula there are extensive deposits of 
sand intermingled with agate pebbles and petrified wood, but these are 
evidently neither derived from the Sinaitic group, nor products of local 
causes known to be now in action. 
I may here notice the often repeated but mistaken assertion, that the 
petrified wood of the "Western Arabian desert consists wholly of the stems 
of palms, or at least of endogenous vegetables. This is an error. I have 
myself picked up in that desert, within the space of a very few square 
yards, fragments both of fossil palms, and of at least two petrified trees 
distinctly marked as of exogenous growth both by annular structure and 
by knots. In ligneous character, one of these almost precisely resembles 
the grain of the extant beech, and this specimen was wormeaten before it 
was converted into silex. 
