164 Geological Observations upon 



rock is a calcareous sandstone, which, as described to me by the 

 chief quarry-man, is arranged in nearly horizontal strata. Between 

 the different layers, there is considerable difference as respects the 

 coarseness of the ingredients ; so that in working it, they are obliged 

 to reject a large portion of the rock, — the variety employed being 

 composed of grains rarely larger than half a pea. The layers of 

 this description he described to me as being thin. It is used in Au- 

 gusta for door steps, window caps, he. and is worked with great ease.* 

 Its color is white, and its appearance is not unlike to that of a fine 

 grained granite, the feldspar of which has become converted into a 

 kaolin. The grains of the quartz are quite angular, the mica is 

 white and in large proportion, while the calcaraeous cement resem- 

 bles chalk or white clay. Intermingled with it, we observe occa- 

 sionally little fragments of black Tourmaline. It passes into a com- 

 pact variety, of a porcelainous appearance, of the precise hardness, 

 color and fracture of the Munich lithographic stone ; and I cannot 

 doubt but that the quarry will afford pieces admirably adapted to 

 this valuable purpose. I searched without success for fossil remains 

 in this rock. 



When at St. Mary's, in Georgia, I was presented with a small col- 

 lection of bones, fossils and pebbles, from the famous Suannee spring 

 in Florida ; and which had been brought up from the bottom by div- 

 ing. They principally consisted of fragments of the teeth and bones 

 of the Sea Cow, {Manatus americanus,) among which are portions 

 of the rib, whose greatest diameter is one and a half inches, and 

 fragments of teeth above an inch long. These remains, as well as 

 the other articles of the collection are coated with a blackish brown 

 covering of a bronze-like appearance, from the precipitation of sul- 

 phuret of iron. 



But the most interesting portion of this collection consisted of the 

 teeth of the shark, spines of the Echinus, and the palates of fishes, 

 one of which is of a form to me entirely new, and another closely re- 

 sembling, if not identical with. Fig. 5, of Palais de differentes especes 

 de poissons inconnus, in the Uidionnaire des Sciences JVaiurelles. 

 In addition to them, I recognised obscurely defined fragments of 

 claws belonging to some crustaceous animal, probably to a species of 

 Cancer, and agglutinated fragments of Ostrea shells. The palates, 

 and these last, were completely silicified. 



* The quarry is the property of Mr. Henry Cummings. The stone when dressed 

 sells for 50 or 75 cts. the superficial foot. The sales for the last year were $3X00, 



