194 GEOLOGICAL SURVEY 
surface, standing as they grew. 'The quantity of timber is often so great as to offer serious impe- 
diments to cultivation, on some rice plantations. 
And this cireumstance—the presence of timber—is sufficient to distimguish these ancient swamps 
from the other recent deposits on the coast, although many of the former have, at present, no trees 
upon them, are overflowed by the tide, and present nothing on the surface different from ordinary 
salt marshes. 'This is the case with a part of Murphy’s Island and Cat (sland. 
It must be borne in mind that these lands are below the level of tide—indeed it is upon this cir- 
cumstance that their value as rice lands mainly depends, in relation to irrigation. 
We may now return to the examination of those changes produced by the encroachment of the 
ocean, and the phenomena which it presents, which have been attributed to the 
SUBSIDENCE OF THE COAST. 
Bartram, in his “Travels,” I believe, was the first to point out the evidences of the subsidence of 
the southern coast, presented in the numerous submerged stumps of trees, so common along the 
shore. Other writers, since his time, have noticed these stumps, and have referred them to the 
same cause; and, more recently, Mr. Lyell has examined the coast of South Carolina and Georgia, 
and has come to the same conclusion, namely, that these submerged stumps “show a vertical 
depression of the land, to the amount of at least four feet.”* 
The whole coast of South Carolina is very low. The tidal wave is felt for a distance of forty 
miles up the rivers from the coast. The most elevated poini of land in the city of Charleston is 
not more than ten feet above tide, and the greater part of the city is not half that elevation: so 
that the subsidence of a few feet would place the whole under the sea. 
Tam inclined to think that a depression of level, to the amount of two feet, would destroy the 
rice plantations, by letting in salt water. 
It was intimated that as the subsidence was of very recent date, it may be in progress at this 
moment. Under these circumstances, and with the prospect before me of witnessing a real case of 
subsidence, where the proofs were so palpable, it will be readily imagined that I set about the 
examination with no ordinary interest. 
» IT will mention, briefly, the most noted localities examined, so that any one may satisfy himself 
of the correctness of the inferences drawn from the evidence they present. 
On the left bank of Little River, in Horry, I saw many acres of marsh overflowed by the tide, 
and covered with Live-oaks, some standing, but the greater number prostrate. The trees were 
evidently where they could not have grown, and it was equally evident that they were not drifted, 
The marsh was nothing but a mud flat, filled with oysters and muscles. It presented, at first 
sight, a remarkable proof of subsidence. Fortunately I continued the examination farther towards 
the mouth of the river, where I found an isolated knoll of sand, washed at its. base by the waves, 
but still supporting a few oaks, which explained the whole. ‘The mud flat was once covered with 
sand-hills, upon which the oaks grew; the waves, during a storm, broke over the peninsula, wash- 
ing away the sand from beneath the trees, many of which were enabled to remain erect, supported 
by their wide-spreading roots. The ocean had simply reclaimed what once belonged to it. In 
* Quar. Jour. Geol. Soc. 
