44 
ELEMENTS OF GEOLOGY. 
The description above given of the slanting position of 
the minor layers constituting a single stratum is in certain 
cases applicable on a much grander scale to masses several 
hundred feet thick, and many miles in extent. A fine exam¬ 
ple may be seen at the base of the Maritime Alps near Nice. 
The mountains here terminate abruptly in the sea, so that a 
depth of one hundred fathoms is often found within a stone’s 
throw of the beach, and sometimes a depth of 3000 feet with¬ 
in half a mile. But at certain points, strata of sand, marl, or 
conglomerate intervene between the shore and the mount¬ 
ains, as in the section (Fig. 7), where a vast succession of 
slanting beds of gravel and sand may be traced from the sea 
to Monte Calvo, a distance of no less than nine miles in a 
straight line. The dip of these beds is remarkably uniform, 
being always southward or towards the Mediterranean, at an 
angle of about 25°. They are exposed to view in nearly ver¬ 
tical precipices, varying from 200 to 600 feet in height, which 
bound the valley through which the river Magnan flows. 
Monte Calvo. Fig. 7. 
Section from Monte Calvo to the sea by the valley of the Magnan, near iMice. 
A. Dolomite and sandstone. (Green-sand formation ?) 
a, b, d. Beds of gravel and sand. 
c. Fine marl and sand of Ste. Madeleine, with marine (Pliocene) shells. 
Although, in a general view, the strata appear to be parallel 
and uniform, they are nevertheless found, when examined 
closely, to be wedge-shaped, and to thin out when followed 
for a few hundred feet or yards, so that we may suppose 
them to have been thrown down originally upon the side of 
a steep bank where a river or Alpine torrent discharged it¬ 
self into a deep and tranquil sea, and formed a delta, which 
advanced gradually from the base of Monte Calvo to a dis¬ 
tance of nine miles from the original shore. If subsequently 
this part of the Alps and bed of the sea were raised 700 feet, 
the delta may have emerged, a deep channel may then have 
been cut through it by the river, and the coast may at the 
same time have acquired its present configuration. 
It is w^ell known that the torrents and streams Avhich now 
