BY E. D. PETERS, JUN., M.E., M.D. 199 
sure to result great beds of kaolin from the action of the decomposing 
sulphides upon the same. I have never seen or read a description of 
Mount Morgan, but after hearing of the rich gold in hematite and beds 
of kaolin I am as certain of the existence of pyrites below as though I 
had seen it uncovered. LEither of these two points prove the existence 
of sulphides below. The single unique feature that Mount Lyell can 
show is the existence of a very extensive mass of very solid oxide of 
iron, containing about as much gold as the pyrites, but tree from silver 
or copper. As itis evident that this ferruginous mass was derived in 
some manner from the pyrites it becomes interesting to learn what can 
have become of the iarge amounts of copper and silver that belong to 
this mass of half-a-million tons or more of iron. Recent explorations at 
a depth of 250ft. seem to have solved this question. For at this point, 
on getting under one corner of the mass of iron-stone on the foot-wall of 
the deposit, a series of shoots of argentiferous copper pyrites have been 
discovered and worked, that are, I think, unparalleled for their richness 
in the history of these low grade ores. The massive copper pyrites is 
sometimes 6ft. or more in width, and not only carries some 6000z. to 
800oz. silver per ton, but is filled with grains, nodules, and masses of 
pure sulphide of silver—87 per cent. silver—sometimes as large as a 
cocoanut, and increasing the bulk value of the ore to something like 
2,0000z,. per ton. Over 100 tons of this ore have already been mined and 
shipped, and we have every reason to believe that we are only on the 
edge of the deposit. I mention this peculiar feature of the Mount Lyell 
mine more to explain how it is that a deposit consisting of such low 
grade ore as I have been describing can ship such extraordinarily rich 
material as the Mount Lyell is known to be now doing, than because it 
has any bearing on the ‘‘ genesis” of the deposit itself. As you see, 
this rich ore is quite a secondary affair, and has no bearing on my 
subject. This completes all that I have to say in this brief paper. 
I must apologise for its fragmentary and unsatisfactory form. But TU 
have been forced to write at sea, and in the intervals of more serious 
labours, I can hardly imagine a more interesting subject for an enthu- 
siastic student of the natural sciences to investigate than this very 
Mount Lyell mine, for there are many minor, though extremely 
interesting and important, points yet to be investigated that I have not 
even touched upon. 
