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PROCEEDINGS OF SECTION C. 497 
affect them. The common strike of the Bethanga lodes is 
between 20 deg. and 30 deg. east of north. They are in reality 
strike faults, cutting the country rock obliquely at a high angle. 
Passing through the different bands of rock in this way is found 
to greatly influence the richness of the lode. Pressure causing 
the folds in the country rock, no doubt defined the lines of 
weakness by drawing out the legs of the curves; a gradual 
horizontal motion then took place, as may be seen by the highly 
polished and striated nature of the (Cangthonschiefer, which 
sometimes occupies the whole space between the walls when in 
gneiss rock ; and also by the striations on the polished faces of 
the quartz when lying on quartz, the striations having a horizontal 
direction, sometimes with a slight dip to the south; also a mineral 
once formed may be found to be broken up and cemented together 
again, giving some parts of the lode the appearance of a quartz 
and pyrites breccia. The lodes have a steep underlay to the 
west. I do not think the rocks have been much displaced by 
faulting, as the rocks on each side of the lode do not ditfer much 
from each other. The dig, partings of clay, and rubbed-off pieces 
of country rock found among the lode material, go to uphold 
the theory of gradual movement, which probably took a long 
series of years. 
The lode is most productive when it passes through belts of 
altered granite of a greenish hue, containing white mica. This 
granite, being unable to give to the strain brought to bear on it, 
has fractured and broken up more than the gneisses, so that 
waters carrying minerals in solution, being relieved of their 
pressure when percolating in the open spaces between the broken 
off pieces of rock, would deposit their over-burden, and would 
also meet with precipitating agents in larger quantities than 
in tighter rocks. When the lodes cross hard garnet gneiss, 
the deposit shows little or no metalliferous minerals. This rock 
seems to have adapted itself to circumstances, and slid over itself, 
forming a series of lenticular masses, containing much chloritic 
minerals, which appear to have served as a lubricant, the lenses 
fitting so tightly as to have left no space for foreign deposits. 
The lodes and rocks in the vicinity of the upper township are 
dislocated by a dip fault, which is occupied by a dyke of amygda- 
loidal diabase. The heave is about 125 yards; this must be a 
horizontal displacement, as the underlie of the lodes is so steep. 
The dyke, which is 8 feet wide, strikes 85 deg. east of north, and 
dips at a high angle to the north. Even where not seen, this 
dyke makes its influence felt ; on driving from the “Gift” shaft 
towards the other side of the gully, the country was found to be 
much broken up, and there was an influx of water ; the dip joints 
of the granite exposed in a quarry near the “ Excelsior” shaft 
are so frequent as we near the dyke as to give the rock quite a 
fissile character. A lode formation in H. Uren’s paddock, situated 
