MINES OF BULL HILL. 
367 
the shafts it is 60° or 70°, but the vein straightens northward to an almost vertical 
position. A small portion of level 2 is said to be driven in volcanic breccia, while 
the workings generally are contained in more or less oxidized granite. 
The vein is ordinarily well defined, with two or more fairly regular walls, which, 
however, are apt to bulge out into swells at places where the ore body is wide. 
Some of the stopes are 25 feet wide. The ore consists of a thoroughly oxidized 
clayey mass, with some pure-white kaolin and a moderate amount of limonite, 
apparently not much more than in the surrounding granite breccia. There is very 
little quartz and the ore can be followed only by assays. The best pay is contained 
in the kaolin seams, some of which run up to $300 per ton, while the hard bowlders 
contain little of value. 
The ore shoot which came to the surface a little south of the Wild Horse shaft 
was very well defined and pitched about 45° N. on the plane of the vein. Near 
the surface the ore w^as low grade and much of this material, suitable for direct 
cyanidation, remains in the upper levels. The length of the shoot along its pitch 
was 1,200 feet, while the horizontal dimension along the levels varied from 200 
to GOO feet; the greatest length being attained on level 5. Good and poor parts 
w r ere irregularly distributed; the richest stope, yielding $200,000, was near the 
bottom, above level 9, 970 feet below 7 the collar; this v r as 40 feet long and 27 feet 
v T ide. Between levels 8 and 9 the ore became stringy and thin. 
Level 10, turned 1,250 feet below 7 the collar, showed the rock unoxidized; 
the crosscutting to the vein w 7 as greatly interfered with on account of gas, wdiich 
sometimes filled the w r hole mine for days. At the end of the crosscut the vein 
w'as found, it is stated, but consisted chiefly of a loose mass of iron pyrites of little 
value. It was not, how-ever, extensively explored. The pyritic granite breccia 
in the crosscut contained values up to $4 per ton. The lower levels have remained 
closed since 1903. 
LONDONDERRY MINE. 
The Londonderry mine is located on Ironclad Hill close to Mkhvay. It has 
not been w 7 orked for many years, and very little ore has been extracted from it. 
The shaft is 300 feet deep, and its collar has an elevation of 10,550 feet. It is sunk 
in granite and schist and some drifts run on a vein presumably parallel to and 
west of the Wild Horse. The workings also extend a few 7 hundred feet east to 
the Wild Horse vein. 
GOLD SOVEREIGN MINE. 
The Gold Sovereign Mining and Tunnel Company owrns several fractional 
claims on the southwestern side of Bull Hill. The company has produced ore from 
tw r o localities, viz, the Lovett vein and the Whisper block. The latter occurrence 
will be described in connection with the Dante mine, as the two properties here 
exploit the same set of veins. The total production to 1904 w 7 as $300,000, of which 
$100,000 w 7 as contributed by the Whisper part of the property. A new and verj^ 
rich shoot w 7 as exploited in 1904 near the Lovett vein. 
The developments consist of the Gold Sovereign tunnel, driven for 640 feet in 
a northeasterly direction, the elevation of the portal being about 10,001 feet, and 
the Jackson shaft, which opens the Lovett vein and is at present leased to the 
