312 Carboniferous Formation of Pennsylvania — Wasmuth. 
plications have been developed, and that these plications, the 
underground contour lines, and some of the cross sections pro- 
duce startling effects. It is true, the maps of the second geolog- 
ical survey of Pennsylvania, to a certain degree are re-construc- 
tions of the mine maps, but the objects of the survey as 
expressed have been: "to afford means to mining engineers and 
superintendents to direct their headings, etc. ;" but I venture to 
say, that the survey has failed to realize these objects, and 1 
will this prove by the following: 
In "bedded" mineral deposits no "inversion" or "over-lapping" 
of the strata can take place without fracture and more or less 
dislocation, and in general, the dislocations of the strata take 
place in one of two ways; either the portion of a mineral 
deposit on the hanging wall of the fracture or fault is in a lower 
position than the portion on the foot 
wall, as illustrated in fig. 1, or it 
is in a higher position as illustrated 
in fig. 2. Occurrences such as those 
illustrated in fig. 1, are called "trans- 
verse faults," while those in fig. 2, are called "longitudinal 
^^ ^ faults," or "over-laps," or "folding faults." 
^'^.A-nf&^ These general theories of "faults" have 
been established by long experience in 
mining in Europe, and are described in 
the report of the first geological survey 
of Pennsylvania, which contains an illustration of a longitudi- 
nal fault, in the blue slates near Wormleysburg, (section of 
the Kittatiuuy valley). 
The second geological survey of Pennsylvania has indicated 
a probable "line of fault" on its maps of the Shenandoah region. 
All exposures of the Carboniferous formation, even in locali- 
ties where it is developed incompletely, or even where it is 
wanting, are of the same geological age, and originally have 
been in a nearly horizontal position. Every change of the 
formation, (or its members) from the original horizontal 
position, in a geological point of view, is termed a "disturbance." 
It must be assumed that the first disturbance of sedimentary 
rock from the horizontal position commenced with the origination 
of shallow anticlinals and synclinals, either by a "lifting" or 
"sinking" of the strata and consequent lateral thrust. I adhere 
