WHITE] rOTTtSVILLE FOEMATION ALONG SHARP MOUNTAIN. 849 



the coals in the sections, the Gold Mine section appears to present the 

 highest degree of agreement with or similarity to the Lorberry Gap 

 section; but, whether the comparison be with the Gold Mine Gap or 

 the Mount Eagle Gap, or the Dundas No. 6 collier}^ tunnel,"^ a few miles 

 to the east of Lorberry Gap, we must conclude that if the South coal 

 represents the Buck Mountain l)ef1 the Lorberry Gap should, in addi- 

 tion, contain a number of the intermediate coals which have been opened 

 in the Black Spring and Rausch gaps. With no other evidence than 

 the measurements of the intervals between the discovered coals on 

 which to base correlations of the latter, an almost equall}^ satisfactory 

 parallelization of the beds might be framed were we to assume that 

 the ''Peacock" coal in the Lorberry Gap corresponds with the first 

 coal above the Buck Mountain bed in the lounger sections to the west- 

 ward. Such an assumption is, however, manifestly untenable, since 

 it involves the reference of the South coal, whose fossils are fully as 

 young as, if not younger than, those of the Buck Mountain bed, to the 

 approximate horizon of the Lykens coal in the Yellow Springs Gap, 

 the fossils from which are referable to the Sewanee zone of the Upper 

 Lykens division of the Pottsville formation. 



1 would have little reliance placed in the foregoing suggestions as 

 to the equivalence of the various coals of the Productive Coal Meas- 

 ures along Sharp Mountain. It needs but an examination of the 

 columnar sections, showing the surprisingly great variation of the 

 intervals between the coals as actually ascertained by direct connec- 

 tions between the mines in the Southern tield," to convince one that 

 correlation of these beds by no other means than the comparison of 

 columnar sections is, in the Southern Anthracite tield, hardlv less than 

 jugglery. 



RATTLING RUN GAP. 



(Station 2-1, Pl. CLXXX.) 



Rattling Run, the most westerly gap in Sharp Mountain, is 15^ miles 

 from Fishing Creek Gap and about -i miles east of the point 

 at which the Pottsville formation begins to spoon out, above Water- 

 tank Station. The. description of this gap, which is about 3 miles 

 west of Yellow Springs, is given with considerable detail in Dr. 

 Taylor's report,* which is quoted in the later State reports.* The 

 principal drifts in the Lower Coal Measures are platted on mine sheet 



1 Section 6, columnar-section sheet viii, Atlas Southern Anthracite Field, Pt. IV. 



2 The variability of the Coal Measures intervals, even between near localities, is well illustrated in 

 the diagram prepared by Ashburner, and published on columnar-section sheet iii, Pt. I of the Atlas 

 of the Southern Anthracite Field. It is also shown in columnar-section sheet vi, Pt. II of the Atlas. 

 Good examples of this are found at the Wood's colliery, and at Dundas colliery. No. G tunnels, cited 

 above, the sections of which are not more than 3 miles distant from each otlier. 



sReporton Stony Creek Estate, iii>. II and 50, pi. ] 17, lijr. 'J. 



^Rogers, Geol. Pennsylvania, \'(il. II. I't. I, \i. i;t7, .Sinitli, Suiiuiiary Final Report, Vol. Ill, Pt. I, 

 p. 2145. 



20 GEOL. I'T 2 54 



