26 GEOLOGY OF OHIO. 



erate is frequently seen occupying a higher level than the coal, but that 

 is also sometimes true of the Waverly. Along the margins of the old 

 coal marshes there were hummocks, hills, and highlands which rose 

 above it, and over these the peat, which has since become Coal No. 1, was 

 not deposited. Sometimes the peat partly filled valleys and narrow 

 channels produced by surface erosion in the Waverly or Conglomerate, so 

 that we now find the coal perhaps a hundred feet below the level of the 

 Waverly, or base of the Conglomerate, but never beneath the true Con- 

 glomerate, or any part of the Waverly. Good examples of this peculiar 

 relation in position between the Waverly, Coiiglomerate, and coal may be 

 seen in Mahoning, Holmes, and Richland counties ; and they are de- 

 scribed in Vol. I, page 128, and in the Third Annual Report of Mr. 

 Andrew Roy, State Inspector of Mines, page 129. 



Second. The error of confounding the Conglomerate below the coal 

 with that which sometimes occurs above. 



In Ohio it (jan hardly be said that a conglomerate anywhere imme- 

 diat.eiy overlies Coal No. 1, but patches of pebbles are sometimes found 

 in the sandstone over the coal in Medina, Trumbull, and Mahoning 

 counties. These are referred to in the sketch of the Carboniferous Sys- 

 tem in Vol. I, Geology, and are supposed to be portions of the gravel-hills, 

 now the Conglomerate — which bordered the coal basin on the north 

 washed down by local streams into the coal marsh, sometimes on 

 to the coal ; but in Western Pennsylvania several of the sand- 

 stones of the Coal Measures become conglomerates. 



THE COAL MEASURES. 



■ 



So much space was given to a discussion of the Coal Measures of Ohio 

 in Volume I, that it will be only necessary here, to review briefly the 

 facts of importance that have been learned since the publication of that 

 volume. 



During the last two years, such developments of the richness of the 

 Hocking Valley coal field have taken place as seemed to require that a 

 more careful study of and report on this field should be made. This work 

 'has been done by Mr. M. C. Read, and the results are given in his report 

 which forms part of this volume. From this it will be seen that the 

 Coftl Measure iron ores have been found to exhibit an unexpected, and 

 it may be said an almost unequalled development there. The iron lies 

 at several horizons, the most important seam being about a hundred feet 

 above the Great Vein Coal, and therefore .on the same level with the 

 Blackband and Mountain ore deposits of Tuscarawas county. In the 

 Hocking Valley the iron ores are chiefly earthy carbonates, frequently 



