164 Geological Observations upon 
rock is acalcareous 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, &c. 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 rernains, 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 espéces 
de poissons inconnus, in the Dictionnaire des Sciences Naturelles. 
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 60 or 75 cts, the superficial fcot. The sales for the last year were $3100. 
