110 
EFFECTS OF 
accompanied by little or no dislocation. The great vein and that 
most remote from it, throw down to the south twelve or fifteen 
fathoms ; the remaining two veins throw down to the north. The 
southernmost vein is remarkable because both the depressed and ele- 
vated beds curve upwards towards the fault. (See Diag. No. 18 .J 
The Marl becks and other veins in Teesdale range mostly east 
and west, and the same prevalent direction (a little north of east) 
is noticed in the mines of Weardale, Aldstone moor, and Derwent. 
Mr. Forster in his account of the mines of Aldstone moor and the 
neighbouring tracts, has the same observation as to the predominance 
of east and west veins. ‘ The fissures or veins of the mines in Wear- 
dale, Allendale, and Aldstone moor, mostly extend from east to west: or 
more properly, one end of the vein points west and by south, while 
the other tends east and by north : although there are other veins 
running nearly north and south, commonly called cross veins : and it 
must be remarked that these cross veins have very rarely been found 
so productive of metallic ores as the others, excepting when the right 
running veins and the cross veins intersect, in which case the cross veins 
generally carry ore for some distance from the place of intersection, 
but very seldom in any other stratum than limestone and especiallv 
the great limestone of Aldstone moor.’ 
Mr. Sopwith observes of this same country ‘most veins in the 
mining district preserve a tolerably direct course for a considerable 
distance, some indeed for several miles. They are commonly designated 
veins, cross veins, and quarter point veins. The former are sometimes 
called right veins, their course being E. and W. or a little N. of E. 
and S. of W. Those which have a bearing nearly N. and S. are called 
cross veins. The few veins which have a bearing between these are 
called quarter point veins.’ 
The prevalence of certain directions in the fissures of veins being 
established, we may next inquire what relation is borne by the plane 
