SUPPLEMENTAL REPORT 
ON THE. 
GEOLOGY OF THE HANGING ROCK DISTRICT. 
Pror. J. S. NEWBERRY, Chief Geologist: 
Drak Sir: I herewith transmit a brief supplemental report on the Geology of the 
Hanging Rock District. The report is based on an examination of the field which I 
made during the summer of 1877, the examination being undertaken under your author- 
ity as chief of the survey, but at my own instance and without compensation. 
The object which I proposed was to trace if possible some ef the well-Enown strata of 
the Hocking Valley southward to the Ohio River, or, to state my object more definitely, 
it was to fullow the great coal seam of the Hocking Valley, and the most important bed 
of iron ore worked there, viz., the Baird Ore, as far southward as they extend within 
the limits of the State. 
IT think that I have accomplished this object in such a manner as to remove all ques- 
tion in regard to the points involved. 
In executing this specific task, I have had occasion to review to some extent the struc- 
ture of the lowest Coa] Measures of the district, but this portion of my work, I count 
incidental. In regard toit, I have to confess that I iave raised more questions than I have 
been able tosettle. There is no peculiar complication or difficulty in the field, but more 
time must be spent on the strata that underlie the Zoar Limestone before a full and 
connected account of them can be given. 
The work that I have done on this portion of the series has obliged me, in some in- 
stances, to form conclusions at variance with those announced in the previous volumes 
of our report. The main points of difference are as follows: 
1. The Conglomerate of Pike and Jackson counties which holds within it workable 
coal—is the Conglomerate of the Hecking Valley which has been proved to be of Sab- 
carboniferous age. There are several divisions of this Conglomerate, but they are all 
included within two hundred feet of vertical range and they all belong to one main 
series. 
2. The Jackson Shaft Coal belongs within tke limits of this conglomerate and is 
therefore of Sub-carbonifercus age. The same thing is probably true of several other 
workable coal seams of the district. 
3. The Maxville Limestone does not constitute the base of the Coal Measures of 
Seuthern Ohio, but its place is from fifty to one hundred feet above the lowest coal 
seams. The Sub-carboniferous age of the limestone is not hereby questioned, but the 
same age is asserted for the lowest Coal Measures of this district. 
Upon these and kindred points, I have accumulated a large number of facts, which 
the proper limits of the present volume, already overrun, forbid me to make use of here, 
