Remarks upon East Florida. 61 



As high as Indian River Inlet, the beach is still formed of shells, 

 though less distinct and perfect in their form, mingled with some 

 sand; while about Cape Carnaverel the sand predominates, until 

 shelly fragments almost disappear to the nalced eye. Still, it 

 seems probable that the whole beach is of a calcareous character. 



The coquina rock (as the Spaniards called it) is a formation 

 found in the spits of sandy land which separate the lagoons near 

 the coast from the sea. It has been quarried in Anastasia island, 

 for more than a century, affording a material for structures of all 

 kinds in St. Augustine, worked with uncommon facility, and of 

 a durable character. A large fort, of Spanish construction, at 

 that place, is of coquina. In latitudes where there is little or no 

 frost, it is, perhaps, the best material that can be used in fortifica- 

 tions ; being firm enough to sustain the form of any work, and 

 receiving a shot like a plastic mass, exhibiting no fracture, and 

 throwing off no splinters. 



The quarries near St. Augustine are generally about ten feet 

 deep. The profile of the strata, as presented to the eye there, 

 exhibits, first, a superficial covering of vegetable mould ; next, 

 a stratum of shelly fragments, quite small, and without any dis- 

 tinctness of character, with no cohesion. This stratum varies 

 much in thickness, according to the undulations of the surface, 

 being generally from two to three feet. The next in the descend- 

 ing series is a stratum of several inches thickness, composed of 

 similar shelly fragments, but united in a mass by some cement. 

 Then intervenes a stratum of sand, an inch or two in thickness. 

 Immediately below this sand is a stratum of shelly rock, between 

 two and three feet in thickness. This stratum is formed of shells 

 in various states, the upper several inches being much like the 

 stratum above, that is, of small and indistinct fragments, when, 

 for several inches more, it assumes a new character, many of the 

 shells being perfect in their outlines, and only much abraded, and 

 most of them of a size to give some clue to their species. The 

 interstices in this portion of the mass are large in proportion to 

 the size of the shells, and the cement which holds them together 

 is hardly visible. Bivalves, cockles, of the cardium species, pre- 

 dominate, while here and there is found a conch of large size, as 

 also oyster fragments. Some of these conchs are several inches 

 in length, .though much worn. This coarse and comparatively 

 unbroken deposit has a substratum, with which it is equally 



