248 GEOLOGY AND GOLD DEPOSITS OF THE CRIPPLE CREEK DISTRICT. 
Quantity of water 'pumped from the Cripple Creek mines from January 1,1S93, to July 1,1902 —Continued. 
Period. 
Moon-Anchor. 
Total. 
Elevation of 
water level. 
Drop in 
water level. 
Amount 
pumped per 
foot of drop 
in water level. 
Gallons. 
Gallons. 
Feet. 
Feet. 
Gallons. 
Jan. 1, 1896, to July 1, 1896 
13,132,800 
13,132,800 
July 1, 1896, to Jan. 1, 1897.. 
40.780,800 
136,857,000 
Jan. 1, 1897, to July 1, 1897.. 
181,735,600 
379,428,800 
July 1, 1897, to Jan. 1, 1898.. 
392,256,000 
9.335 
Jan. 1,1898, to July 1. 1898. 
52,876,800 
517,547,200 
9,305 
30 
17,251,573 
July 1,1898, to Jan. 1.1899. 
236,192,000 
1,234,252,400 
9,285 
20 
61,712,620 
Jan. 1, 1899, to July 1,1899. 
285,120,000 
4,580,895.600 
9,242J 
42$ 
107,785,779 
July 1.1899, to Jan. 1, 1900. 
3,680,948,800 
9,172J 
70 
52,584,983 
Jan. 1. 1900. to Jnlv 1. 1900_ 
2,744,655,200 
9.137J 
35 
78,418,720 
Jnlv 1. 1900. to Jan. 1. 1901__ 
2,540,174,400 
9,102J 
35 
72,576,411 
Jan. 1,1901, to July 1,1901. 
1,892,160,000 
9.082J 
20 
94,608,000 
July 1, 1901, to Jan. 1, 1902. 
908,828,000 
9,057 
25J 
35,640,313 
Jan. 1, 1902, to July 1, 1902. 
984,268,800 
9,035 
22 
44,739,491 
Total. 
809,838,000 
20,005,405,000 
300 
a 66,684,683 
a Average. 
Mr. Mudd was compelled by lack of data to disregard the considerable flow from 
the Ophelia tunnel. He also omits from his calculations the probably small quan¬ 
tity of water that sinks into the ground each year and the water pumped from the 
Gold Coin and Stratton’s Independence mines, probably because he considered these 
mines as outside of the area affected by the drainage tunnels. His general conclu¬ 
sion was that the quantity of stored water decreases as greater depth is attained. 
Recently Mr. A. C. Jaquith® has estimated that during the four weeks ending 
April 10, 1904, the average discharge necessary to lower the water in the Elkton 
mine 1 foot was 34,839,775 gallons. This, taken in connection with Mr. Mudd’s 
figures, indicates that there is less water in the lower part of the subterranean reser¬ 
voir than above. It is certain, however, that the water in the Elkton and Mary 
McKinney mines is lowered more rapidly by the tunnels than in other mines less 
favorably situated, so that a fall of 1 foot in the Elkton does not mean that the 
entire surface of the reservoir has subsided to the same extent. These estimates, in 
short, are at best very rough approximations to the truth. 
The volumetric ratio of the water-bearing spaces to the rock mass as a whole 
can not be determined from existing data. It has been shown that in the spring of 
1904 a discharge of approximately 35,000,000 gallons corresponded to a fall of 1 foot 
in the Elkton and Mary McKinney mines. If the entire volcanic neck were affected, 
if the volcanic rocks everywhere permitted the free passage of water, and if the 
inclosing granite, gneiss, and schist were quite impervious, it would be a compara¬ 
tively simple matter to estimate the approximate area of any given horizontal 
section of the neck and then to calculate the percentage of water-bearing spaces. 
These conditions, however, do not obtain. The rocks are practically impermeable 
except where fissured, and the eastern part of the volcanic neck is but slowly affected 
by the drainage of the western part. The rock mass drained by lowering the water 
“ Oral communication. 
