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which the first gold-digger has relinquished as worthless, a 
constant and remunerative supply of gold can be relied on. 
It is otherwise, the Author believes, with the true gold mines, 
those in which the auriferous quartz reef is worked. Here 
the supply is, as far as we know, unlimited — the assertion 
that the quartz reefs became poorer in gold as they descend 
being as yet quite unproved, so that when the due combi- 
nation of science and capital has been brought to bear upon 
the subject, there seems to be no reason why the auriferous 
quartz reef should not be followed as far as any other metal- 
bearing vein, as in the Cornish tin mines or in the silver 
mines of Mexico and Peru. Hence the Author concludes 
that the supply of gold from Australia will probably continue 
to be large and regular. 
In the discussion which followed the reading of the Paper, 
Mr. Binney, Mr. Hull of the Geological Survey, and Pro- 
fessor Roscoe took part. 
Professor Roscoe remarked, that he believed the chemical 
investigation of the silurian schist in the neighbourhood of 
the granite or quartz dykes would probably throw some light 
upon the dark field of metamorphic actions. We should 
probably then see that the mineralogical character of the rock 
had been totally altered by the action of the neighbouring 
quartz-reef, whilst the chemical composition had sufiered little 
or no change. 
Mr. Binney stated that Mr. Jevons’s description of the 
Australian gold fields reminded him of the quartz views in 
the silurian rocks of Seathwaite, near Broughton-in-Furness, 
in this country, which were auriferous, and which had 
several times been proposed to be wrought for gold. In 
Australia, as well as in Lancashire, the quartz views were in 
silurian deposits in the vicinity of granite; in the latter 
country near the granitic district of Ravenglass. The size 
of the quartz views here had prevented their being wrought 
with success. Had they been as large as the reefs of 
