460 REVIEWS—GEOLOGICAL SURVEY OF CANADA. 
While large blocks of the Acton conglomerate give thirty per cent. and upwards 
of pure metal, the best blocks obtained by me from the conglomerate of Upton do 
not yield more than five per cent. But this, if the quantity of rock with such a 
per centage were large, and the masses not too widely scattered, would constitute 
a valuable mine. It would, however, require a careful crop trial to determine 
whether the quantity is available. 
“On a recent visit to the Harvey’s Hill Mine, I was informed by Mr. Williams 
that, after sinking on the incline N. 80 E. <75°, on Fremont’s lode, near the top 
of the hill, for forty-five feet, the underlie changed to S. 80 W. <75°, and the 
shaft being then sunk vertically for seventy-five feet more, a bed of three inches, 
holding disseminated copper ore, was met with at the depth of twenty-five feet; 
and another of six inches, of the same character, fifteen feet further down—the 
latter constituting the top of a six-feet bed of soapstone. In this an opening 
was made for thirty feet each way in the slope of the bed, which met Fremont’s 
lode in the rise, and continued beyond it. At the bottom of the incline a level 
was driven in the bed for nearly thirty-two feet. The copper ore was continuous 
the whole of the distances, and may be said to have thus been proved over an 
area of nearly 2,000 square feet in the plane of the bed. 
“The shaft being full of water at the time of my visit, I had not an opportu- 
nity of inspecting the work; but descending another shaft, at a distance of about 
ten chains from the last, in a direction which is nearly in the dip of the strata, 
I examined what there is little doubt must be another bed. This occurs at a 
depth of ninety feet from the surface ; and allowing for the fall in the surface be- 
tween the two shafts, its position would be very nearly twenty fathoms above the 
upper bed in Fremont’s shaft. An opening has been made in the bed of about 
seventy feet in length by twelve feet in width, partially on the strike, but gradu- 
ally turning up to the full rise of the strata. In this opening, the thickness of 
the bed, as measured by myself, varies from nineteen to thirty inches. The rock 
is a nacreous slate, and the copper ore is distributed in the bed in patches gener- 
ally of a lenticular form. They are usually thin, but sometimes attain from one- 
half to three-quarters of an inch in the thickest part; and occasionally present in 
the section, lines of six inches or even a foot in length. These patches interlock, 
one overlapping another, with variable distances between, while many single 
crystals and small spots of ore are disseminated throughout the whole thickness, 
In some parts the pyritous, and in others the variegated sulphuret, prevails, and 
the quantity of metallic copper in the mass may range from about three to about 
five per cent, producing an average of about four per cent. The estimate, how- 
ever, has been made by the eye and not by assays. Supposing the bed to average 
two feet in thickness, a cubic foot to weigh 180 pounds, the produce to be five per 
cent., and one-fifth of the copper to be lost in dressing the ore up to twenty per 
cent., then each square fathom of the bed would yield 1.10 tons of dressed ore of 
the above produce, the value of which in Swansea would be about $110. If the 
produce were four per cent., the value of a fathom would be $88; if three per 
cent., $66. It is only by an experiment on a large quantity of ore, in the way of 
dressing, that the true produce of the bed can be determined. 
“The mode in which the copper ore is distributed in the nacreous slates of 
