64 Phosphate Rocks of South Carolina, 
The quantity taken from this pocket was estimated 
at several wagon loads. 
We supposed them to be Coprolites, or the fossil- 
ized excrements of some of those large Aquatic Mam- 
malia of that age, whose bones are found in great 
numbers in the Marl, and also mixed with the Phos- 
phate-rocks in the basins. The Zeuglodons, Squalo- 
dons and Phocodons, swarmed in the waters of that 
period, and they had as associates huge Crocodiles or 
Alligator-like creatures, which roamed the submarine 
forests like an army of Locusts seeking their prey. 
The amount of Phosphate of Lime found by Dr. 
Pratt, in his analysis of these supposed Coprolites, is 
small compared with that of the Phosphate-rocks, 
being only 15 per cent. But it is not surprising, as 
the Marl must have extracted a large portion of their 
phosphoric essence. 
This completes the history of the Marls and the 
Phosphate-rocks up to the close of the Confederate 
War in 1865, and which for four years excluded 
all Europe, their doings and their publications, from 
Confederate eyes; and it was not until 1867, when 
we had recovered sufficiently from the effects of the 
war to import a few books from England, was ascer- 
tained what had been done during the interval by 
scientific men in that country. 
Early in the month of August, 1867, the oth or 
1oth day, our friend Dr. N. A. Pratt, with whom 
we had been intimately associated during the war, 
brought us a small fragment of rock and enquired if 
we knew it. We replied yes; as well as we know 
