é 
On the Gulf Stream and the Keys of Florida. 57 
- Stowth would be found. Here, therefore, would be formed a 
barrier reef, limited on one side by the muddiness, and on the 
other by the depth of water. 
It is evident then that the Peninsula and Keys of Florida 
have been the result of the combined action of at least three 
agencies. First, the Gulf Stream laid the foundation; upon this, 
corals built up to the water level; and finally the work was com- 
pleted by the waves. Fig. 4 illustrates the relative importance of 
€se¢ agencies. All below the line nn/n''n'”, even to the bottom 
of the Gulf Stream, is due to the agency of that stream ; all be- 
een the line n n/ nn’ and the line /J to the agency ol corals 
and above the line ZJ to waves. A 
haking a ent 7 
side of the curve. This is certainly true; but it 1s a more gen- 
Still water will deposit sediment on both sides, just where it 
comes in contact with the still water, and is retarded by it. It 
Mississi 
form of submarine banks, ieueaty formed by the checking of 
the Velocity of the current on either side by contact with the 
“\ Water of the Gulf. t. 
SECOND SERIES, VOL, XXIII, NO. 67.—JAN., 1857, 
8 
If the current is straight the deposit on - 
* 
