366 GEOLOGY AND GOLD DEPOSITS OF THE CRIPPLE CREEK DISTRICT. 
ALBANY TUNNEL. 
The Albany tunnel, on the northwestern slope of Bull Hill, starts about 1,200 
feet southwest of Midway station and is at an elevation of about 10,170 feet. Its 
course is S. 68° E. and it runs for about 1,400 feet in brecciated and oxidized granite. 
Shattered zones carrying kaolin and manganese are frequently seen, running in 
various directions. About 700 feet from the portal an 18-inch basalt dike strikes 
N. 40° W. and dips about 80° SW. The dike is much broken up, and the rock 
decomposed as usual. No ore has been found in the tunnel. 
The Happy Year tunnel was described under the Happy Year mine. 
WILD HORSE MINE. 
The Wild Horse mine, which is controlled by the Woods Investment Company, 
is situated on the northern side of Bull Hill. Ore was discovered in it in 1897, 
and it was actively worked until 1903, when development in depth ceased. At the 
present time the upper levels are leased and low-grade ore for direct cyaniding is 
extracted. It is stated that the production has somewhat exceeded $1,000,000, 
and that about one-fourth of this amount has been disbursed in dividends. 
The developments are very extensive; the vein has been followed for a distance 
of 2,400 feet on various levels. The mine is opened by the Wild Horse shaft, the 
elevation of the collar being 10,653 feet. The lower levels are principally opened 
from the Gleason shaft, which has the same elevation of collar and which is 1,250 
feet deep, level 10 being turned at that depth. Drifts and crosscuts will aggregate 
between 2 and 3 miles in length. The mine never had any water, general drainage 
having preceded exploitation. 
The Wild Horse vein outcrops near the eastern contact of the isolated area 
of more or less shattered granite which occupies the western part of Bull Hill and 
the southern part of Ironclad Hill. Fragments of plionolite are sometimes found 
in this granite and may be due to dikes wholty crushed by secondary movements. 
The rock is oxidized to a depth of 1,150 feet below the surface. As shown in 
the crosscut on level 10, the fresh rock is a loosely cemented breccia, the fragments 
being usually a few inches in diameter and containing plentiful disseminated 
crystals of pyrite. In places a little fluorite may be noted. The contact between 
granitic and volcanic breccia is more or less indistinct on the surface and is not 
exposed in the mine; however, the volcanic breccia usually contains a large amount 
of granitic detritus. Schist begins to appear in the hanging wall of the vein on 
level 4, underneath the Midway station, according to Messrs. Finch and Purington, 
and there are also one or two dikes of plionolite in the older rocks. 
The Wild Horse vein is remarkable in several respects. It is curved, striking 
north-northwest in its northern portion, between Midway and the Wild Horse 
shaft. South of that point it assumes a north-northeast course, and has been 
traced for 1,000 feet to a point not far from the Ramona shaft. Near the Wild 
Horse shaft the apex of the vein lies practically on the contact between granitic 
and volcanic breccia, though it does not follow this contact in depth, but north 
of this point it enters the granitic area. The vein has been traced to a point under¬ 
neath the gap at Midway. The dip is generally steep toward the west. South of 
