Carboniferous Formation of Pennsylvania — Wasmuth. 321 
the thicknesses of sedimentary rock will have to be subjected 
to corrections. 
A glance at the maps of the western middle coal field of 
the second geological survey of ^ Pennsylvania will convince 
one of the great number of anticlinal and synclinal folds 
similar to the one that occurs in the Panther Creek region, 
mentioned already. I maintain that perhaps with a few 
exceptions, they will be developed to be longitudinal faults, 
just as the occurrences in the Panther Creek region, etc., are. 
It is beyond doubt that longitudinal faulting is very frequent 
and predominant in the anthracite region, just as transverse 
faulting is predominant in the Pittsburgh region. As none of 
the existing faults are represented on the maps of the survey, 
it is obvious that they have not been recognized, and that 
therefore the contour lines on the maps, valuable as they other- 
wise might be, are illusive; because contour lines of the surface 
are the results of adequate surveys and underground contour 
^>9- 
lines, especially in such a disturbed district, cannot be con- 
structed beyond existing mine workings. That the faults of 
the anthracite measures have not been recognized by the 
geologists in charge, but rather the total absence of faults 
pronounced by them, is proven by a paper re-printed from the 
Mining Herald. 
The industry of anthracite mining might properly be con- 
sidered as the art of " controlling coal land companies," and 
" controlling mining companies." 
The anthracite lands, to a great extent, were possessed by the 
Pennsylvania-German farmers and the excellence of anthracite 
as a domestic fuel and for manufacturing purposes in connec- 
tion with the I favorable topography induced them to make 
numerous openings in the ravines, etc. The construction of 
railroads and growing industries promoted increased demand for 
fuel and the organization of large coal land companies, thus 
