.8
the
great wealth in gold met with at points of junction of slate and cross
lodes would have never reached the cross lode. In fact, all evidences
available tend to prove—-(1) that the rocks, particularly the slate,
of this State's gold-fields have been permeated with gold ; (2) that
these rocks were corrugated and heated to temperatures that admitted of
the extensive cracking in them ; (3) that the systems of cracking have
evidently been arranged in accordance with the thrust imparted by the
movement of the granite, coupled with the movement engendered by
expansion of the sedimentary rock, due to the heat of the granite ; (4)
that the descending water, meeting with the heat of the granite,
resulted at times in a profuse extension of dyke matter up the lines of
least resistance (the crack lines) to the surface ; (5) that the
temperature of the earth's skin which admits of cracking, admits of
water in the cracks being liquid ; (6) that water passing through all
rocks, upwards and downwards, seeks the lines of least resistance to
its passage ; (7) that, as it soaks through the rocks and circulates in
passages, it takes up or deposits quartz and metallic minerals in
accordance with the conditions, chemical or mechanical, governing it
for the time ; (8) that the influence or force of gravity appears to
have had a distinct influence in arranging the form of the deposit; (9)
that resistance to circulation, partial or otherwise, is essential to
the deposition of gold ; (10) that the more nearly horizontal the floor
of the obstruction, particularly to the drainage channels in almost
vertical layers of slate, the more concentrated or nuggety the deposit
of gold:
(11)
that the more nearly vertical the floor of a situation for deposits,
provided it has partial obstruction at each end and below it, the more
scattered the gold deposited on it, that is, dragged down by gravity in
a long shoot :
(12)
that no situation of the latter description contains much gold if the
situation is not associated with slate layers, and even when it is
associated with slate, if the latter has floors of veiu obstruction
passing out from the main body of quartz through it, it is not so rich
in gold as it would be otherwise, as the floors act as filter packs and
retain most of the gold going through the drainage lines before
reaching the main channel.
In
all of the mining centres visited in the district under notice, the
washdirt miners of the fifties were the pioneers. They made their marks
everywhere, and succeeded collectively in unearthing immense wealth,
although the patchy nature of the gold deposits in the washdirt beds
caused a very unequal distribution of this wealth amongst the miners
engaged. The lode structure throughout the whole area being of the
twist strain order, there is much of the wing and fin-like quartz
occurrence belonging to it, and, as this means coarse and nuggety gold,
there were found lumps weighing 100 lbs. and over, and lumps weighing
from 10 to 1)0 lbs. often came to light. It must not be supposed that
the richest washdirt always travelled to the deepest parts of the
valley, for all the lumps of gold, and a large proportion of the finer
gold, were met with on or close to
