Wadsworth.] 
94 
[November 17, 
1°. Where tongues of the hanging wall trap extend down 
into the “ ash bed ” the latter rock has become indurated, and is 
neither amygdaloidal nor copper-bearing to any extent ; but had 
these infiltrations taken place prior to the succeeding flow, this 
flow ought to have made no essential difference in the amygda- 
loidal and copper-bearing character of the “ash bed” in such 
places. 
2°. Spikes of copper, known as “ ash bed ” spikes, extend 
down out of the hanging trap into the ash bed. These spikes are 
usually larger at the upper end, and sometimes branched, while 
they are pointed at the lower end. 
Is it possible for us to imagine that the sandstones and con- 
glomerates, the jiebbles of trap in the conglomerate, and the “ ash 
bed,” could have retained their original heat until they were 
impregnated with copper as described? Some of the conglom- 
erates have been filled with and altered to an epidotic material, 
which change must have taken place since the rock was laid down 
on the beach, for this alteration extends to the conglomerate as a 
whole and not to its individual pebbles only. 
The part of these old lava flows that retained their heat 
the longest, i. e., the heaviest beds, and the bottoms of all the 
flows, ought, according to Professor Dana’s hypothesis, to have 
suffered the greatest alteration, and to carry the most copper 
outside of the cavities, but exactly the reverse is the case. It is 
the upper part of the “ ash bed ” that is worked for cojjper, and 
the upper part of the traps that is most altered. 
As evidence that materials are altered when they do not retain 
their original heat, the fact can be pointed out that fragmental 
volcanic rocks have become 2>seudo-amygdaloidal and metamor- 
phosed as a whole since they were in a fragmental condition. 
Furthermore it is not supposed that the old Roman bricks 
retained their original heat until the zeolites were formed in 
them, as described by Daubree. 
After the eastern sandstone and the western (in part at least) 
with the intervening traps and conglomerates were laid down, the 
fissures were formed that have since been filled with mineral 
matter, making the veins. Some of these veins have been traced 
for miles and all cut directly across the beds of conglomerate and 
