PROFILE OF THE SUBAQUEOUS SHORE TERRACE 27 
on almost any of the coastal charts of the United States Coast 
and Geodetic Survey. The east coast of Florida furnishes typi- 
cal illustrations. 
Normal profile; cutting coast—TVhe normal profile then, of a 
shore where the resultant of transporting power is outward, is a 
compound curve, which is concave near the shore, passing 
through a line of little or no curvature, to a convex front. 
Where this front rests upon the bottom below the reach of cur- 
rents, the descent merges into the more level bottom by another 
concave curve, due to deposition from suspension. If the sup- 
ply of material from the shore be cut off, the entire shelf will 
be cut down and its slope reduced and it will necessarily be 
separated from the shore by a steeper slope than before. If, 
on the other hand, the supply of material be suddenly increased, 
a smaller shelf will grow from shore on the surface of the older, 
for the reason that the new load, being greater, is in equilibrium 
with the currents at a higher level than before. The greater the 
load, the nearer will the surface of deposition approach that of 
the water. On the Atlantic coast of the United States, the depth 
at which the concave curve merges into the plane of deposition 
varies from three fathoms near the mouths of some rivers, to ten 
or twelve fathoms where the lead is smaller. On some parts of 
the Pacific coast, where the lead is small, the concave curve 
descends to twenty or thirty fathoms. 
Normal profile; building coast.—If the resultant of shore action 
be to carry material landward, the general character of the 
resulting curve cannot be very different, since this process also 
produces steepening near shore. In general the velocity of 
shoreward motion increases with nearness to land. If the 
effectiveness of this motion increases with its velocity, there 
is no accumulation until the shore is reached. The shore is 
then progressively steepened by accumulation, until the force 
which acts shoreward can no longer carry material up against 
the growing component of gravity. This landward urging of 
sediments is commonly thought to be one of the factors in the 
production of off-shore barriers. It is plain, however, that 
