23S 
[Assembly 
7. Tentaculite limestone. 
8. Water limestones, 
9. Pyritous slates. 
Near New-Baltimore, Coxsackie, and thence on by Catskill, Kings- 
ston and Rochester, the principal masses of this formation are similar 
to those of Becraft's mountain, near Hudson, and contain the pentame- 
rus hmestone, tentaculite hmestone, and water limestone. In some 
places the sparry limestone* and shale are found in addition to the pre- 
ceding, which are the principal extensive strata of this formation, in 
the district under examination this year. 
Econoviical applications of the materials of this group. 
The materials in the Helderberg limestone group, that are applica- 
ble to useful purposes, are, 
1. Limestones, for building stone, 
2. *' marbles. 
3. " " common lime, 
4. Cement rock for hydraulic lime. 
5. Pyritiferous slate, for alum, copperas and sulphate of lime. 
Building stones and mar'bles. 
The pentamerus, tentaculite and water limestones, all afford fine 
building stones, which can be procured in blocks of large size, perfect- 
ly solid, and free from cracks or flaws, in many parts of the range of 
these rocks, which extends in a curved line 140 miles. Through this 
long distance, the outcrop of these rocks is not concealed more than 20 
or 25 miles, and this only at intervals of a few miles, where they are 
covered by the tertiary and alluvial deposits of the Mamakatting valley, 
between Rochester and the Delaware river at Carpenter's point. 
Numerous quarries may be opened near to water transportation, for 
the supply of the New-York and other markets, from the High 
Rocks" above Kingston point, by Rondout, Eddyville, Rosendale, Law- 
renceville, High-Falls, Rochester and Wawarsing, and which shall be 
within a few rods to one half mile of canal or river navigation. 
Strata of these rocks are from a few inches to 3 feet thick, from 
which the stone can be taken out in regular and sound blocks of almost 
any desired size. 
* See note-on page 237. 
