SUBTERRANEAN MOVEMENTS, &c. 117 
into an elliptical section; two such systems would probably produce 
the curious phenomenon of an elliptical elevation or depression, corres- 
ponding to the (locally) predominant set of joints, bounded by contrary 
depressions or elevations, parallel to the other set. This remarkable 
result is illustrated in the whole Ribblesdale system, at Greenhow 
hill, &c. 
W ere the elevating or depressing force perpendicular to the planes 
of stratification and applied in a 'particular line, the stratified masses if 
uniformly thick, and yielding with general uniformity along this line, 
would occasion an anticlinal ridge or a synclinal trough ; and parallel 
breaks and bends would be occasioned, their distances, numbers, and 
extent depending on the character of the joints, the thickness and elas- 
ticity of the stratified masses, and the degree of force employed. 
Were such forces applied in a line to extended masses of unequal 
resistance, the effect might be in one part an anticlinal, in another 
a synclinal axis, in a third a great fault, and the lines might not be 
straight. (The same effects might happen at the boundary of a large 
elevated or depressed district.) 
Were the forces applied uniformly to a great area of horizontal 
rocks, uniformly resisting, axes of displacement rectangulated to one 
another but of indeterminate direction must happen if there were 
one system of open joints, this would determine a primary axis of 
displacement, and by consequence secondary axes also, for as the primary 
displacement is supposed limited, any further fracture not parallel to 
it would be most easily effected along the shortest line from one of its 
parallels to another. If in addition we suppose a second system of 
joints this must greatly influence the lines of secondary fracture : 
unequal loading of the strata might change the axes of primary and 
secondary elevation or depression into a great fault and cause them 
to bend or zigzag in their course. 
It appears then that the direction and character of displacement 
