COAL FIELDS. 277 



3. Lower Kittanning coal. 



2. Upper Clarion coal. 



1. Lower Clarion coal ( Brook ville). 



The only change made in this enumeration from the order named in 

 Volume V is in the replacement of the term,"Brookville" by "Lower 

 Clarion." 



Professor Lesley, in his final review of the Pennsylvaina coal fields 

 has found it necessary to recognize a tri-partite arrangement of the coal 

 seams of the Lower Coal Measures as follows: 



{Upper. 

 Middle. 

 Lower. 

 (Upper. 

 Middle. 

 Lower, 

 f Upper. 



Clarion Group 1 M.ddle. 



( Lower. 



The Ohio coal seams can be well enough provided for by a bi-partite 

 system, as indicated above; though it cannot be denied that occasional 

 representatives of the extra Pennsylvania seams are found within our 

 limits. The questions in regard to the exact correlation of these extra 

 seams are, of course, open ones. The leading seams named above will 

 be briefly reviewed in the order of their formation, but for a more 

 extended account of the facts pertaining to them, the reader is referred 

 to Geology of Ohio, Volume V. 



The Clarion Group. 



1. Lower Clarion or Brookville Coal. This seam underlies the 

 Putnam Hill limestone. It is best developed in Stark county, where it is 

 mined under the name of the Limestone coal. A full account is given 

 of it in Volume V, p. 230, to which the reader is referred. The same 

 seam is mined in a very small way at Zanesville within the city limits. 

 It has acquired no new importance since the date of the last review. It 

 adds so little to our fuel resources, that it would scarcely be missed if it 

 were dropped from the scale. 



2. Upper Clarion Coal. The coal seam which directly underlies 

 the Ferriferous limestone is confined to the southwestern extension of 

 the Ohio coal field for the reason that the limestone itself is limited to 

 this district, so far as a generous development of it is concerned. Ttie 

 limestone makes its first appearance as a thin and inconstant bed in 

 Perry county. It gains strength and steadiness through Hocking county 

 and comes to itself in Vinton county, extending thence in full force 

 through Jackson, western Gallia and Lawrence county, to the Ohio 

 river. In Vinton, Jackson and Gallia counties, the limestone coal, as 

 this seam is universally called, is an important local source of fuel. It is 

 beginning to be appreciated as a possible basis for mining in the large 

 wav, and the lands containing it are now being gathered in considerable 



