W. J. MeGee—Elements in Orographic Displacement. 277 
contraction of the globe might give rise to a fault, which, as 
indicated not only by physical considerations but also by the 
testimony of existing faults, would form an angle with the 
vertical,” At the same time the region (A) on the side of the 
fault forming an acute angle with the surface would be u 
heaved, and the region (B) on the opposite side depressed. 
Such a displacement might altogether relieve the tangential 
strain. The elevation and depression on opposite sides of the 
fault may each be assumed to equal ». Suppose now the 
upheaved portion of region A to be removed by denudation 
and deposited within the depressed region B. The thickness 
of the crust at A and B will then be o+p and n+n+o+p 
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go a further depression, while the lighter area would be corre- 
: 2d+2d+3d+4d . 
99 while that of region B is only — 1 
obvious that the former region will be depressed and the latter 
elevated; and the relative elevation of the two regions will 
t is 
peroxystmal in its nature and occurring at the close of a perio 
ay operative repose and quiet sedimentation. 
>ince the secular refrigeration of the globe would eventually 
