184 GEOLOGY OF OHIO. 
The intervals will be seen to match fairly well with the facts 
already recorded. They are as follows: 
1 2. 
Clarion (Upper Coal wc. ccsecscccesecsescscsecesesvsccusidcvsopscesessccresceces 102 96 
Mercer (UippershoOrizoniy. co cstc-<cosecccseccccescecconaaoecetecoscmecnaitesssees AO 41 
Mercer Lower limestone ...............scsecseeseeeeeveees iueseskiaameaeeeees 0 0 
The horizon of the Block coal lies 150 feet below the “ bottom 
rock,” so called. There seems but little reason to expect workable 
deposits of the lower seam so far within the field as this point, but no 
test of its presence has yet been made. 
The error of counting the Canfield cannel seam and the Leetonia 
coal as one and the same has extended to adjoining townships, and 
especially to Beaver and Springfield. The seam called No. 4, in Spring- 
field, is the Lower Kittanning or Leetonia seam, while both coals are so 
named in Beaver as they have been shown to be in Green. 
Tt is of interest to note that the largest and most important field of 
the Clarion coal in Ohio is found in this immediate region. Beginning 
at Canfield, it extends as far southward as New Lisbon. While the 
quality is inferior, it still makes an important contribution to the fuel 
of the State. The time will come when the nicer shades of quality will 
no longer be available, or when at least cheaper grades of coal will be 
sought for various uses. This seam may await a full development when 
these conditions are reached. 
II. COAL MINES OF COLUMBIANA COUNTY. 
According to the census tables of 1880, this county held the 4th 
rank among the coal-producing counties of the State, its output for the 
"census year being 541,466 tons, and 18 large and 16 small mines being 
reported. The general geology of the county has been quite fully 
treated in volume III, and the details of its more important coal fields, 
which are there given, can be adopted in the present report, subject to 
the same rectification of geological order that has already been applied 
in the present report. 
