SUPPLEMENTAL REPORT—HANGING ROCK DISTRICT. 897 
blue. It occasionally resembles certain phases of the Putnam Hill Lime- 
stone very much, but its distance from this in the scale renders any con- 
fusion from this cause unnecessary. The only limestone with which it 
is really likely to be confounded is the Ames Limestone that lies about 
one hundred feet above it. : 
6. The Ames Limestone—The last of the series is the stratum called 
the Ames Limestone by Prof. Andrews, from the township of this name 
in Athens county. It is a light gray, crystalline, highly fossiliferous 
limestone, often crinoidal, that is found in all of the Coal Measure coun- 
ties of the State in which it is due. In the district under consideration, — 
however, it is but seldom reached. Its altitude above the Cambridge 
Limestone, in the Hocking Valley, varies in the few sections measured, 
between eighty-five and one hundred and twenty-one feet. The interval 
in two sections in Gallia county was found to be one hundred and forty 
feet. It is often called the “fossil limestone,” or the “crinoigal lime- 
stone.” It will answer an excellent purpose for furnace flux. In this 
district, at least, it does not pass into flint. 
‘The Ames Limestone forms the summit of the series to be considered 
here. 
ACCESSORY SEAMS. 
Between the Ames and the Cambridge Limestones, one of the accessory 
seams named on a preceding page is due, viz., the Ewing Limestone. It 
has not been seen where the interval between the limestones named 
above is shortest, but in the Sunday Creek Valley it is found at about 
eighty feet above the Cambridge. It does not vary ten feet from this 
interval throughout the field. It is quite heavily charged with iron, is: 
non-fossiliferous, and weathers easily. It is often found in isolated 
bowlders in a seam of red earth along the line of outcrop. It is con- 
cealed by the products of its own decomposition, much more than any 
other limestone of the series. : 
Between the Hanging Rock and Shawnee Limestones, two seams of 
buff limestone are often found. Neither is steady in occurrence, but the 
upper one, named the Norris Limestone, marks an important horizon. 
A valuable ore seam is found at this level in the southern part of the 
district. The Norris Limestone,in the Hocking Valley, seldom reaches 
a thickness of two feet. 
The lower of these two seams, called the Snow Fork Limestone, is 
found af comparatively few points. On the Snow Fork of Monday Creek, 
Hocking county, however, it is shown in numerous outcrops, and has 
been counted available in that region for possible furnace use. It lies 
only twenty or thirty feet above the great coal seam of the valley. 
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