A Strati graphical Study 
141 
ments; he states® that the fossils were ‘‘identified by Mr. Meek as 
belonging to the carboniferous formation.” If the fauna is found 
to be Maxville, then we can understand how^ the degradation of 
this horizon in early Pottsville time might account for its presence 
in the Sharon. A very careful search has been made both in this 
township and in Perry township directly east, but no Maxville 
limestone was found. This fossil content of the Sharon conglom- 
erate affords an interesting problem. 
(2) About two miles west of Mary Ann Furnace during the 
early seventies, a thin vein of coal was worked on the “Baker” 
place; the same horizon apparently was also worked on the road 
leading southwest across this high area. At this latter place the 
coal vein was buried by only a few feet. This coal horizon appar- 
ently had a very irregular horizontal distribution; in an outcrop 
between the two localities above mentioned, its presence is only 
suggested by a “blossom.” 
In one more place there is evidence of a former shallow coal 
working. This is at the top of the grade west of Mary Ann Fur- 
nace reached by taking the first road bearing to the north, and is 
near the corner made by this highway meeting one from the south. 
Just west of the corner reddish shale is found subjacent to fire- 
clay; a few rods farther, we find more of this clay and a “blossom” 
above it. 
On the supposition that the Logan formation in this area is not 
thicker than in the Mary Ann Furnace section, i. e., about 100 feet 
it follows that we have here 160 feet of Pottsville; in the absence 
of a definite contact between the Sharon and Logan, only this 
method remains for obtaining, even approximately, the thickness 
of the Pottsville. 
b. Sedimentation 
(i) The outlines of former land areas, and their altitude, may 
be indefinitely inferred from a study of the rocks. The constancy 
in the thickness of a given formation; a variation in its texture, 
horizontally and vertically; its structural peculiarities, whether 
genetic or imposed later, if any; its life, whether marine, littoral, 
or continental, whether prolific, sparse, or stunted; all tend to defin- 
ing the continents of the past. Furthermore, the constancy or 
® Geological Survey of Ohio, vol. iii, pp. 545-46, 1878. 
