THE COAST REGION. 17 



It tlien becomes a marsh and is taken possession of by the marsli reed, to 

 be succeeded, when the debris collected by their growth has raised the 

 locality above high water, by tufts of rushes. Meanwhile seaward, the 

 sands, first pushed up against the outflowing current of the river by the 

 ocean, are dried by the sun, and then blown forward and heaped into 

 hills and ridges, forming a protection against the encroachments of the 

 waters whence they came. Every breeze blowing landward carries along 

 with it particles of fine sand, till they meet with a log or bush, or other 

 obstacle, when they begin to accumulate in proportion to the velocity of 

 the wind, sometimes with extraordinary rapidity — piling up and running 

 over the top, rising in ridges and hills to the height of thirty or even of 

 forty feet. The prevailing winds of this region, the southwest and north- 

 east, are indicated by valleys running in this direction through these 

 hills." 



In the manner thus described, the salt water of the ocean being ex- 

 cluded, the surgent island is prepared for the growth of fresli water 

 plants, such as the cypress and other swamp trees, while pines and pal- 

 mettoes, the advance guard of the vegetable kingdom, establish outposts 

 wherever a few inches of intervening sand renders them safe from im- 

 mediate contact with sea water. 



This theory will also account for certain topographical features observed 

 on these islands and in their vicinity. The highest land is usually found 

 on the margin of the island. A fact which, viewed in connection with 

 the general observation that the banks of streams are higher than the 

 adjacent alluvial lands, strongly sustains the vieAV of their deposition from 

 river currents. The prevailing shape of the islands is triangular. The 

 apex is directed southwest, often terminating in marshes, while the higher 

 and dryer base faces northeast. From Mr. Tuomey's observations, it 

 appears that it is the sandbar on the northeast that first rises above the 

 waves, remaining the most elevated, while the growth proceeds in a south- 

 westerly direction. This southwardly growth results from a deflection of 

 the river current that is transporting the material of which the island is 

 to be formed. Whether this deflection toward the right (or the southwest) 

 be due, as Prof. Kerr thinks, to a force arising from the earth's rotation, 

 which deflects all moving bodies to the right in the northern hemisphere, 

 or to the prevailing south westwardly current along these shores, or to 

 both, it is certain that such a deflection clearly exists. Seaward it may 

 be clearly noted in the charts of the coast survey in the depositions now 

 taking place at the mouths of the rivers. The ship channels are always 

 found to the south of the harbors. Inland, the south and southwest bend 

 of the rivers has been already mentioned ; and coupled with it is the 

 observation made long since by Mr. Ruffin, that the blufts are on the west 

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