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EFFECTS OF 
having been filled, and its accompanying displacement fixed, fresh 
fractures took place transversely, which displaced the strata along certain 
planes parallel or coincident on both sides of the cross vein, with 
equal dislocations in the same direction, yet did not traverse that 
vein at all, but caused a general sliding along its planes. This com- 
plicated hypothesis contrasts very unfavourably with the simplicity 
of the former popular opinion, and involves more than one impro-' 
bability. 
Yet there are particular phenomena occasionally occurring in a 
mining district, at the intersection of veins, which are somewhat em- 
barrassing on either view. For it sometimes, but not often, happens 
that a divided vein is ramified on one side of the cross vein, that 
another is continued beyond the intersection for some distance in a 
new plane, and then resumes its old course, — that others change their 
throiv at a cross course. 
The ramifying of a vein on one side of a cross course, can perhaps 
only be explained upon the popular view by supposing it an accidental 
coincidence ; veins are often ramified, and cross courses are frequent ; 
such coincidences then ought not to be thought surprising. Werner 
appears to have thought that such cases implied openness of the 
divided fissure at the time of the formation of the cross vein. 
The continuation of a vein in a new plane, for a short distance, 
is usually accompanied by a considerable lateral displacement, not 
explicable as a case of vertical dislocation of an inclined plane ; such 
an oblique translation of great masses of strata may be expected to 
produce other singular phenomena. 
Ihe change of throw at a cross course, if not an accidental coin- 
cidence, can only be explained by admitting for such particular vein, 
a displacement contemporaneous with the cross course, or posterior to 
it. The instance given by Mr. Forster is equally compatible with 
either opinion, as may be seen by turning his plan into a vertical 
section. 
