Geological Survey of the State of New York. 105 
cepted, the group consists generally of argillaceous materials in 
the lower part, and carbonate of lime in the upper part. ‘The 
red shale forms the base or lowest mass of the salt springs found 
along the course of the Erie Canal in the third district, and has of- 
ten been confounded with the red sandstone of retin and its pro- 
longation, the-sandstone of Rochester and Ni iagara. The two 
rocks, being separated by the Protean group, have no connection 
With each other, nor resemblance, excepting that the same fer- 
ruginous material colors them both, and both are connected with 
saliferous sources.” This rock “ increases greatly in thickness” 
from east to west, and from a boring in Lenox of two hundred. 
feet, just north of hills of shale two hundred feet high, attains 
here a thickness of four hundred feet, “ yet no where has a fossil or 
a pebble been discovered in it, or any thing extraneous, excepting 
a few thin layers of sandstone and its different colored shales.” 
The second deposit is an alternation of variously colored shales, 
contains fibrous gypsum of a reddish or salmon color, and the ex- 
cavations of wells exhibit the same products as are found in dig- 
ging for salt water at Abingdon, Virginia, in a salt valley. No 
wells of water are obtained in this or the next deposit, on the 
hills, unless sunk below the level of the water courses, and there- 
fore no brine springs could be found above this level, owing to 
the permeable nature of the strata. The only fossil j is a small 
Cytherina. 
The third or gypseous deposit, contains the extensive and val- 
uable deposits of gypsum in insulated masses, never in layers and 
beds, in two distinct ranges, and separated generally by the “ ver- 
micular lime-rock of Eaton, th the ‘happetshapad eavitiogy and. ath: 
er porous rocks.” 
This group affords the only pant that saithonecisted. here i in 
a solid state, though never has a particle been discovered in the 
rock, and it is the only known source of the brine springs of the 
district. 
The vermicular rock is “a dark gray. or bine rock, perforated 
every where with curvilinear holes, but very compact between 
the holes, some of them lined with a calcareous crust,” and one 
of the porous rocks affording water lime, consists chiefly “of 
and carbonate of lime grains,” and “passes into a po- 
rous Seallnlex sponge-like rock, without carbonate of lime, but 
abounding in organic remains.” ‘“'The cavities of these porous 
Vol. xxx1x, No. SAGE Sime 1840. 14 
