MARBLE. 
69 
remains, which give it a variegated and beautiful appearance. It also frequently presents, on 
fracture, that singular columnar structure, at right angles to the layers, which has been quite 
aptly compared by Mr. Vanuxem to the sutures of the skull. In consequence of a suggestion 
made by that gentleman,* that the appearance in question was owing to sulphate of magnesia, 
I subjected a specimen to analysis, and found its composition to be as follows, viz : 
Carbonate of lime,. 75.65 
Carbonate of magnesia,. 20.70 
Silica and alumina,. 2.25 
Oxide of iron,. 0.35 
Moisture and loss,... 1.051 
Oneida County. In this county we have the Trenton limestones, which will furnish beau¬ 
tiful black marbles ; and the grey marble near the Holland patent, and on a branch of Steuben 
creek. 
Onondaga County. In this and the adjoining county (Madison), the grey crinoidal lime¬ 
stone affords a marble scarcely excelled by any in the country for beauty, durability, and the 
fine polish which it receives. The quarries in Onondaga county are moreover very extensive, 
and yield blocks of great size. The marble is not only used for ornamental purposes, but in 
its dressed state is employed in the construction of locks, aqueducts, and other similar struc¬ 
tures. The public works recently constructed in the vicinity of Syracuse present a striking 
proof of the superiority of this material over that formerly used for similar purposes, while at 
the same time they offer a no less striking illustration of the great advances which have been 
made in the arts of construction in this State. 
I have analyzed two specimens of the grey crinoidal limestone, the one from the quarry near 
the Chittenango falls in Madison county; the other from the Split Rock quarry in Onondaga 
county. The following are the results — No. I. is from the former, No. II. from the latter : 
I. 
II. 
Carbonate of lime,. 
98.50 
99.30 
Oxide of iron,... 
0.35 
0.20 
Insoluble matters (silica and alumina), . 
0.90 
0.40 
* New-York Geological Reports, 1838. 
t I have also analyzed a specimen of limestone from the bed of the river at Rochester, Monroe county, called “ Calciferous 
Slate” by Prof. Eaton, and “Calcareous Shale” by Mr. Hall. It is bluish grey, a little crystalline, and emits a strong bituminous 
odour when struck or subjected to heat. Its composition is, 
Carbonate of lime, ..... 44.65 
Carbonate of magnesia,.. 30.00 
Silica, with a little alumina,.... 24.00 
Oxide of iron, . 1.00 
Bituminous matter. 0.30 
This bituminous matter occurs in many of the limestones which I have examined. It is found in the residuum unacted on by- 
acids, and, when subjected to heat, gives out an odour resembling that of burning peat. 
