1086 GEOLOGY OF OHIO. 
‘less valuable than the Pittsburgh coal field in Ohio, but inasmuch as the latter is 
already extensively occupied and developed by mining industries, and consequently 
is well known as to character and capacity, I have judged it best to use the few pages 
of space available in the present volume for the upper coals, in a description of the 
-comparatively unknown and undeveloped seam, the extent and character of which 
have now been briefly indicated. Mr. Brown’s map and report show very clearly 
the areas, thickness and quality of this seam, and few questions in regard to the field 
are left unanswered, so far as its availability for mining operations is concerned. 
A large amount of information has been gathered by the present Survey in 
regard to the coal seams above the Mahoning sandstone, but inasmuch as the volume 
has already passed beyond proper limits, not even asummary of these results can be 
‘furnished here. E. O. 
