242 GEOLOGY AND GOLD DEPOSITS OF THE CRIPPLE CREEK DISTRICT. 
In PL XX an attempt is made to show graphically the behavior of the under¬ 
ground water in the principal mines. A large number of facts, many of which have 
been collected by Messrs. Hills and Mudd, might be cited in illustration of the lack of 
sensitive adjustment of water surface over the district at large to changes artificially 
produced at any one point. A few examples only need be here adduced. 
In July, 1903, the water in the Portland mine stood 557 feet above the pump¬ 
ing level of the adjoining Stratton’s Independence, and had been stationary for 
several months. In April, 1904, the Portland water had fallen only 26 feet, not¬ 
withstanding the facts that pumping has been continuous in the neighboring mine 
and that the El Paso tunnel had been draining the district for seven months. In 
August, 1903, the Portland water was falling from 2 to 3 inches a week. The rate 
evidently increased after the completion of the El Paso tunnel, but how much of 
this increase is to be ascribed to the tunnel and how much to the increased pump¬ 
ing necessitated in Stratton’s Independence mine by the development on level 14 
can not be determined. It is probable, however, that the tunnel has aided in 
lowering the Portland water. In April, 1904, the Elkton water was 15 feet lower 
than the Portland water, whereas in July, 1903, it was 17 feet higher. In July, 
1889, according to Mr. Mudd,® the Portland was pumping 1,500 gallons a minute 
from the 800-foot level, while the Elkton, 40 feet deeper, was dry. According to 
Mr. Hills , b the Clyde mine, on the east side of Battle Mountain, pumped water for 
over a year in 1900-1901, from an elevation of 9,573 feet, when the Modoc, Last 
Dollar, and Portland mines, its near neighbors, were dry at lower elevations. The 
Eclipse mine, between the Portland and Elkton, had, on April 19, 1904, a water 
level 491 feet above that of the Portland, 520 feet above that of the Ajax, and 
506 feet above that of the Elkton. This, as Mr. Hills has pointed out, is one of 
the most remarkable cases of difference of water level to be found in the district. 
It is in a way more striking than the greater discordance between the Portland 
and Stratton’s Independence levels, because at this time neither the Eclipse, Port¬ 
land, Ajax, or Elkton were pumping, and there was supposedly sWe opportunity 
for hydrostatic adjustment. 
The history of the underground water in the Elkton mine is particularly inter¬ 
esting from its illustration of the fact that the water circulates mainly through 
open fissures and not through the general mass of the country rock, and from the 
close connection of this mine with the drainage tunnels. The following account of 
the Elkton water is based upon carefully prepared data which were very kindly 
' furnished us by Mr. Sherwood Aldrich, chairman of the executive committee of 
the Elkton company. 
The first water encountered in the Elkton mine was on level 3, 9,423 feet above 
the sea. The flow ranged from 400 to 600 gallons per minute, but after a few 
months the level became dry, owing probably to drainage through the Ophelia 
tunnel. The flow on level 4 was similar to that on level 3, while successively larger 
amounts of water were encountered on levels 5 and 6. These levels also ultimately 
became dry, being probably drained by the Standard tunnel. In 1900 sinking 
was continued and stations cut at levels 7 and 8. Pumps were placed on level 8 
and drifting was begun from both stations. In February, 1901, the south drift on 
a Manuscript report to the Elkton company. 
b Ninth Ann. Rept. Portland Company, 1903, p. 89. 
