which form the opposite Walls of Cross-veins. 447 
course, which dips N.E. 50°, and also Glover’s lode, which 
dips S.. 50°—80°; whilst it heaves Paul’s lode, which dips 
N.W. 50°—70°, from 15 to 18 feet at different levels, and 
Michell’s lode, which dips S. 80°, 3 feet, and both of them 
towards the right-hand (2). 
We have here two veins, the elvan and Glover’s lode, dip- 
ping in opposite directions, and both simply intersected ; and 
two others which have also opposite inclinations, and are, never- 
theless, heaved in the same direction, but to unequal distances. 
Now a horizontal motion (1.) would have heaved them all 
the same distance, and in the same direction; and a vertical 
movement (2.) would have heaved Glover’s and Michell’s lodes 
in one direction, and the elvan-course and Paul’s lode in the 
opposite: whilst a motion on the line of inclination of Glover’s 
lode would have occasioned a heave of the elvan-course, as 
well as of Paul’s and Michell’s lodes; on the other hand, if 
the line of elevation or subsidence had coincided with the dip 
of the elvan-course, it must inevitably have heaved Glover’s 
lode (which has an opposite dip to the elvan), together with 
Michell’s and Paul’s lodes. 
We have thus, within a very few fathoms, two sets of facts 
equally contradictory to each other, and to all the directions 
of motion we have yet assumed: nor does any circumstance 
indicate that any other motion could be substituted with greater 
probability of overcoming the difficulty. 
(B.) At Cardrew Downs, two elvan-courses dip W. 50°— 
60°: both of them are intersected, both by the Little and the 
Great flucans, but they are not heaved by either. ‘The south 
lode dips N. 60°—s0°, and the north lode dips S. 68°—82°. 
The Little flucan heaves the former 24 feet at 50, and 60 fa- 
thoms deep, and 30 feet at 100 fathoms; and the latter 15 
feet at 50, 70, and 80 fathoms deep, and 12 feet at 60 fathoms. 
All the heaves are towards the right-hand. 
Now if the heaves had been consequences of horizontal 
motion (1.), not only would all of them have been of the 
same extent, but the elvan-courses would have been heaved as 
well as the lodes. Ifthe motion had been a vertical one (2.), the 
lodes would have been heaved in opposite directions, and both 
the elvans would have been heaved also. As, however, the 
elvans are not heaved, any motion must have been parallel 
to their inclination (s7, Pl. LV. fig. 11). Now, in order to 
produce a heave of 24 feet at the south lode by an elevation 
parallel to the dip of the elvan, a movement of from 25 to $0 
feet in extent is requisite; whilst a motion, similar in direction 
and distance, would produce a heave of between 5 and 6 feet 
in the north lode, whereas the observed heave is 15 feet. This 
