98 MASSACHUSETTS AGRICULTUEE. 



of its commercial value. The geological position of these 

 beds, as strata, had long been known and described, but it 

 has been only within the j)ast few years that their extreme 

 richness in phosphate of lime has classed them as among the 

 most valuable mineral beds of South Carolina. More than 

 twenty years ago our learned Professor Agassiz, attracted by 

 the numerous fossils, named a certain locality ^*The fish-bed 

 of the Charleston basin." But his attention, like that of other 

 distinguished naturalists, seems to have been given rather to 

 the physical characteristics than the chemical composition of 

 these "nodules" or "conglomerates." 



The immense marl deposit underlying this rock had been 

 frequently analyzed, and w^as known to be comparatively rich 

 in phosphate, yielding nine or ten per cent. The discovery 

 of this amount of phosphate in the marl, making it equal, if 

 not suiDcrior, to the New Jersey marls, led many to apply it 

 freely to their lands with good results, and some, suspecting 

 some hidden and unknown fertilizing agents in the nodules 

 or rock itself, pounded these also and apj)lied them freely, 

 though with less beneficial results. This was more than thirty 

 years ago, and at that time phosphates, artificial fertilizers and 

 superphosphates were almost unknown in that section. In 

 fact guanos in this country had been in use but a short time ; 

 hence the anxiety of scientific men was to develop the great 

 masses of calcareous marls which were found in South Caro- 

 lina and Georgia. Under these circumstances it is perhaps 

 not strange that a rock, containing a very low per cent, of 

 carbonate of lime, should have remained unknown, so far as 

 its chemical composition was concerned, and no careful an- 

 alysis of these nodules seems to have been made until August, 

 1867, five years ago. 



During the late war Southern men of learning and ability 

 were put to their wits' end, by reason of the blockade, to pro- 

 vide and manufacture various articles for which they had been 

 dependent upon importation. Among these was nitre, which 

 enters so largely into the manufacture of gunpowder. "While 

 searching the banks of the Ashley and Cooper Eivers, in pur- 

 suit of this material, a distinguished chemist of Georgia had 

 his attention from time to time attracted by the novelty of the 

 appearance of this rock, and the abundance of the fossils 



