8 Phosphate Rocks of South Carolina, 
Phosphate-rocks, but fossil ‘eet and fossil dones ; and 
that, too, notwithstanding their richness (when thus 
associated) in Phosphate of Lime. 
When we speak of Mart, we mean simply “that 
compound of earthy mixtures of which Carbonate of 
Lime, in any form, constitutes either the sole or the 
chief value as a manure, and which is in such large 
proportion as to be an important value, and the mass 
soft enough to be excavated and broken down by 
ordinary digging utensils.” 
GREEN SAND often contains no Carbonate of Lime; 
is not generally rich in calcareous matter, and there- 
fore should be called GrEEN-sAND Marv. Mart- 
STONE is calcareous, of a stony hardness, and not 
capable of being dug, because not of an earthy tex- 
ture ; cannot be pulverized enough by ordinary imple- 
ments to be used as a manure, but requires-for such 
purpose to be burnt to lime. It is truly a LIMESTONE, 
and should be so called. 
Cay is a soapy, non-calcareous, earthy material, 
but there are some forms or varieties that are impro- 
perly though popularly termed Marl. 
CopROLITES are the undigested fecal remains of ani- 
mals, fossilized; of stony hardness; often petrified, 
and sometimes, though not often, phosphatic when 
_ taken from Tertiary or modern rocks. 
CONGLOMERATES are strictly commingled fragments 
of many kinds of rocks, or they may be termed loose 
materials of a rocky character cemented together in 
masses. The conglomerates of the Ashley Beds are 
made up of Phosphate-rocks, Marls, Pebbles, Gravel, 
