552 WESTERN COAL MEASURES AND INDIANA COAL. 
without doubt, to the Mahoning sandstone. In fact, the mis- 
placing of coal seams, and confounding of sandstones at all levels 
with the Mahoning sandstone, of Pennsylvania, and the Anvil 
Rock sandstone of Kentucky, I might continue to trace through- 
out the entire coal field of Kentucky, Indiana and Illinois. In 
the Kentucky reports, and the Report of a Geological Reconnois- 
sance of Indiana, 1859, as well as in the reports of other geolo- 
ists, who have written on the western coal measures, the 
distinguished authors appear to have satisfied themselves that the 
western coal beds and sandstones are synchronous with the Ap- 
_ palachian strata, and that the Mahoning sandstone, there a con- 
spicuous horizon, must, as a matter of necessity, have a place in 
the western field, and divide here, as there, the measures into up- 
per and lower coal measures, and that the coal beds should con- 
form thereto. 
Having pointed out a few of the errors committed in the stratjg- 
raphy of the Indiana coals, at localities where their position can 
be proved beyond a doubt, I will now proceed to show some of 
the errors that exist in the Kentucky column, from observations 
made at the same localities that furnished the data upon which it 
was constructed, and which column has heretofore served as a 
basis for the arrangement of the coal beds and sandstones of all 
other districts in the west. 
The column of the coal measures given at pages 18—24, 3d vol., 
Geology of Kentucky, presents us with thirteen hundred and fifty 
feet of strata, above the Millstone grit or Careyville conglomerate. 
From the sandstone under coal No. 18, down to the Anvil Rock 
sandstone, there is a repetition of the strata, including the latter. 
rock, probably as far down as No. 7.. This part of the column 
was constructed from bores that started on the Carthage lime- 
stone, which, in Union county, Kentucky, is, I now believe, the 
equivalent of the limestone over coal No. 11. Though the details 
of strata passed through in these bores can hardly be relied upon, 
and in no two instances do they fully agree, as to the character of 
the rocks, still the place of the coals, and probably their full 
thickness, is given with considerable accuracy. Therefore, in the 
arrangement of this part of the column, it was erroneously as- 
sumed that the bottom of the lowest bore in Union county, start- 
ing from the horizon of the Carthage limestone, stopped just be- 
fore reaching coal No. 11. From No. 17 down to No. 13 by ref- 
