398 
GEOLOGY OF THE FIRST DISTRICT. 
in Schenectady county, near the Erie canal, a few miles from Amsterdam, for building, flag¬ 
ging and curb stones, for the New-York, Albany, Troy, and other river markets. It is also 
quarried for stones for locks and aqueducts. It is a durable and valuable stone for such 
purposes. 
At Glen’s falls, on the Saratoga side of the Hudson, it is quarried for a black marble. It is 
easily obtained in large blocks within a few rods of the marble mills, where it is sawed into 
slabs and other suitable forms for fireplaces, tables, window and door caps and sills, etc. Mr. 
Rice, the proprietor, was sawing at the time of my visit one thousand feet per week, and 
thought the amount sawed in 1840 would be fifty thousand feet. This marble is mostly 
shipped to the New-York market. The supply is inexhaustible ; but in proportion as they 
quarry farther from the banks of the river, the amount of earth and rock necessarily removed 
to uncover the marble beds will be greater, and the expense 'increased. Some of the beds of 
this rock are burnt for lime. One of the strata of this rock at Glen’s falls shows marks on the 
upper surface of the layers, like those produced in soft mud by drops of rain falling on its 
surface. Similar facts have come under my observation in other places. 
The Trenton limestone has not been recognized more than three or four miles northeast of 
Sandyhill, the subjacent limestones coming in contact with the Utica slate. 
The junction of the Trenton limestone with the Utica slate, has already been mentioned as 
capable of being seen at low water of the Hudson, on the Saratoga shore above Baker’s falls. 
Gentle swells or undulations of the rocks are seen between Baker’s falls and Glen’s falls. 
The strata are well exposed between those points, and nearly horizontal. 
The following section, taken by Cadet Truman Seymour, is supposed to afford a good idea 
of the nature and relative quantities of each of the rocks of this group in that vicinity : 
Section near Glenns falls, Saratoga county. 
No. Description of the strata. Feet. Inches. 
1. Thin layers of limestone alternating with compact slate- 20 0 
2. Two layers of compact but rather coarse limestone_ 4 0 
3. Fine black shale_ 0 5 
4. Thin layers of limestone alternating with compact slate--— 20 0 
5. Compact limestone, one layer_ 5 6 
6. Ditto ditto in four or five layers _ 7 0 
7. Ditto ditto in very thin layers_ 8 6 
8. Compact slate- 0 6 
9. Compact limestone, containing fossils_ 1 6 
10. Ditto ditto containing fucoids, indistinct- 2 0 
11. Ditto ditto in thin layers, thickness unknown. 
69 5 
The strata numbered 2 and 5 are worked for marble and building stones. 
In No. 3, a fine encrinite was found, perfect; and at the marble quarries, long spines in 
