450 Mr. Henwood on the Rocks and Veins 
Let us compare these demands of theory with the facts ob- 
served :—At 
108 fms. deep, both lodes are simply intersected by one cross-course. 
ORE both lodes are heaved to the left-hand by one cross-course, 
and to the right by the other. 
ia wa both lodes are simply intersected by both cross-courses. 
le pe vais both lodes are simply intersected by one cross-course. 
‘Similar results, at the same levels in both lodes, whether 
intersected by one or both of the cross-courses, appear in 
every instance; except at 146 fathoms deep, and there one 
lode is simply intersected, whilst the other is heaved towards 
the left-hand. 
These facts seem utterly irreconcilable with the result of mo- 
tion in any one single direction that can possibly be assumed. 
But we have not always simple intersections to indicate the 
directions in which any elevatory forces must have acted. In 
the absence of the guidance such examples afford, it will be 
requisite to ascertain whether the observed conditions may or 
may not be fulfilled by motions which are neither horizontal, 
vertical, nor yet coincident with the dips of any of the veins, 
but oblique to them all. 
Very little consideration will convince us that heaves in the 
same direction, but of very different distances, may in this 
manner be effected by motion of the same extent and direc- 
tion ; as it will act on the lodes according to the coincidence 
or obliquity between their dips and the direction of the move- 
ment. Such a state of things, arbitrarily selected in order to 
suit the circumstances, may often be applied to the heaves of 
two lodes by the same cross-vein, when in the same direction, 
but of unequal distances. But the sufficiency or insufficiency 
of this hypothesis is tested by its affording, or not, in a third, 
fourth, or fifth intersection by the same cross-vein, the same 
coincidence between theory and fact as were obtained in the 
first and second. 
(F.) At Wheal Prudence an elvan-course dips N. 45°, and 
appears in the face of the cliff: the north lode dips N. 68°— 
80°, and the south lode dips 8S, 68°—85°. The cross-course 
heaves them all towards the right-hand,—the elvan-course 30 
feet, the north lode 9 feet, and the south lode distances differ- 
ing at different levels, and varying between 18 and 30 feet (g.) 
A horizontal motion would have heaved all the veins to the 
same distance; a vertical movement would have heaved the 
south lode in a direction opposite to the others; and a motion 
coincident with the dip of either would have occasioned a 
