TACONIC SYSTEM. 
429 
of the ledge, and nearly its whole length, the line of junction of this rock with the slate can 
be most perfectly traced; but at the north end it appears to terminate abruptly against the 
slate, and in some places has the appearance of having been deposited on the top of its lami¬ 
nar edges. From the manner of termination, the appearance of slate in the vicinity, and the 
occurrence of a small valley a little north and transverse to the direction of the strata, I was 
induced to suspect the presence of a fault, and that the limerock might again be found on the 
opposite side of the valley, unless the dislocation had been very great.” “ Having ascended 
the acclivity to the north, I found again the same stratum of rock imbedded in slate, and 
pursuing the same direction. I traced it north a little distance beyond the line of Stephen- 
town. The general character of the slate in which the limestone is imbedded is distinctly 
talcose; and on the east face of the ledge, where I first observed that stratum, is a locality 
of what Prof. Eaton has described as alum slate, where the rock is falling to pieces by the 
decomposition of iron pyrites.”* 
At Lebanon springs, the contact of the slate and limestone was not seen; but a few rods 
southeast of the springs, Mr. Briggs saw it within a few feet of their junction. Some of the 
slaty variety of the limestone is so much intersected with fissures, that the slaty character is 
scarcely discernible. 
A stratum of sparry limestone was seen by Mr. Briggs on the East mountain in Canaan, 
between the Shaker village and the line of Massachusetts, imbedded in slate, and in some 
places interlaminated with it. “ The slate in which the limestone is imbedded is rather talcy, 
and easily falls to pieces. The slate, at a little distance on either side of the limestone, is 
of a much coarser and stronger texture, and not so easily affected by atmospheric agents ; so 
that the limerock and the soft slate form a kind of valley parallel to the general direction of 
the mountain range.”! “ A little south of the south Shaker village in New-Lebanon, is a 
ledge of the slaty kind of sparry limestone, imbedded in a very talcy kind of slate dipping 
east-southeast about sixty degrees. A few rods east of this place, the slate is coarser, and 
distinctly chloritic. The limestone has been quarried for burning into lime by the Shakers, 
and can be traced about thirty rods.”! The position of the rocks of this valley can be seen 
in the sections, PI. 13, figs. 4, 5, 
A quarry has been opened in the slate, southeast of the south Shaker village in Canaan. 
The rock splits out in broad plates suitable for flagging. It is talcose, but the talc is mostly 
between the layers. 
The limestone is seen in small knobs, one-half or three-quarters of a mile southeast of Hatch’s 
tavern, and the contact with the slate may almost be seen. A section across the valley from 
the East mountain (or Hancock mountain) to the flour mill on the outlet of Whiting’s pond, 
shows the following rocks. They crop out through the alluvial, drift and quaternary, so that 
the order of superposition is not seen, and they dip to the E.S.E. 40 to 65°. 
♦ Geological Notes of the New-York Survey, Vol. \i, pp. 341, 345. 
t Manuscript Geological Notes of the New-York Survey, Vol. 2, p. 348. 
t Ibid. p. 354. 
