WATER-LIME GROUP. 
141 
13. WATER-LIME GROUP. 
Water-lime Group of Manlius (Annual Reports). Water-lime rock? Eaton. Tentaculite 
limestone. 
(Part of No. 6, Pennsylvania Survey.) 
The only locality in the Fourth District where the rocks of this group are known to con¬ 
tain their characteristic fossils, is in the town of Phelps, Ontario county. Near Vienna vil¬ 
lage, and at Maffit’s quarry, about two miles northeast of this point, are some thin layers which 
succeed the rock usually burned as water-lime, and which is the upper part of the salt group, 
as before stated. These layers contain the fossils typical of the group. It is understood that 
in the Third District these fossiliferous layers embrace the rock burned for hydraulic cement, 
whence the name of the group. 
In Schoharie county, where these fossiliferous layers are well developed, they embrace no 
hydraulic limestone, and the salt group lies immediately beneath them, the more compact 
portion of which is known as the water-lime. 
In the Annual Reports of the Fourth District the term water-lime has been applied to the 
terminal mass of the last group, as being that rock from which hydraulic cement is prepared 
in numerous localities, and possessing all the essential qualities of that substance. The rock, 
therefore, known as the water-lime throughout the counties west of Cayuga lake is described 
as the upper division of the salt group, and which according to the Report of the Third Dis¬ 
trict does not correspond with the water-lime of that portion of the State, but with the mag¬ 
nesian deposit of the Onondaga salt group. 
These explanations seem necessary to a right understanding of the matter, since it is 
desirable if possible to render a description of the rock under the name by which it is com¬ 
monly known. 
The strata identified by their fossils as the water-lime group consist of thin courses of 
dark colored or bluish limestone, often not more than half an inch thick, and when struck by 
the hammer emit a ringing sound. The characters are much the same as this rock presents 
where it has been examined further east. The Favosites which are usually an accompaniment 
of this group when fully developed, do not appear here. 
The thin layers when exposed to the atmosphere present numerous linear cavities, which 
cross the surface in all directions and cause a destruction of the mass. When freshly ex¬ 
posed or when a layer is split, the centre will be found presenting the same linear cavities 
containing acicular crystals of sulphate of baryta. These, as the stone becomes exposed are 
dissolved and the cavities left. The crystals and cavities cross the fossils as well as the other 
parts of the stone separating them into numerous divisions. 
