used for Agricultural Purposes. 
421 
the city of Charleston, contained phosphatic nodules in great 
abundance. 
This bed or stratum. Dr. Pratt says, has been long known 
in the history of the geology of South Carolina as the Fish Bed 
of the Charleston Basin. It is found outcropping on the banks 
of the Ashley, Cooper, Stono, Edisto, Coosaw, and Combahee 
rivers, or their tributaries ; but it is developed most heavily 
and richly on the Ashley, and no doubt extends along the coast 
east, and especially west, to unknown limits, and has been found' 
as far inland as forty or fifty miles. 
According to the same authority, the bed varies from 17 to 18 
inches in thickness, sometimes, though rarely, increasing to two 
or three feet, and in some places it thins out to a few scattering 
nodules on or near the surface. It consists essentially of indu- 
rated, irregular-rounded nodules, buried in an adhesive and 
tenacious blue clay and sand ; sometimes, however, it exists in 
continuous beds, or large lumps, or conglomerates of soft chalky 
consistency, as if it had been originally a soft pasty mass of phos- 
phatic mud, that has since become semi-consolidated. Asso- 
ciated with these are a most wonderful assortment of animal 
remains, among which bones of marine animals are so abundant 
as to have induced Professor L. Agassiz, twenty years ago, to 
call it " the Fish Bed of the Charleston Basin." 
But the chief supply of phosphate of lime is not to be found 
in the fossil bones, but rather in the nodules, which appear 
to constitute in some places from one-third to one-half of the 
entire weight of the stratum. 
The area of the bed containing phosphatic nodules in work- 
able quantity is stated by Dr. Pratt to be not less than 40 or 50 
square miles. The phosphatic nodules lie along the water- 
courses of the country, over the area mentioned above ; on the 
banks of the rivers and smaller steams, and of the swamps now 
or formerly discharging their waters into these streams ; and are 
not found in any abundance or available quantity beyond 400 
or 500 yards from the water-courses and swamps. They are 
generally found in the detached deposits at very irregular in- 
tervals along the banks. The means requisite for making even 
a rough approximation to the area they actually occupy are not 
easily attained, and probably they occupy less ground than has 
been stated. 
The phosphatic nodules are generally rough, and irregular in 
lorm, water-worn and rounded, and of light yellow or brownish 
colour; they are tolerably soft, cavernous, often perforated by 
boring shells, and show casts of fossils. Fish teeth and frag- 
ments of bones are also frequently associated with them. 
There are two kinds of Charleston phosphate, the land and the 
