42 
Colorado Experiment Station 
There are some very important questions which have not yet been 
touched upon, or if they have been suggested, they can be put much 
more plainly. We have given analyses of artesian waters from the 
town of Alamosa, others from the town of Mosca. The difference in 
altitude between these two towns is 15 feet. The intervening coun¬ 
try is without known folds or faults, the distance is less than 14 
miles, and yet the artesian water at Mosca is wholly different from 
that at Alamosa. This is true for all the different flows encountered 
at the respective places, which may be illustrated by the Electric Light 
well at Alamosa and the Mill well at Mosca. The former has a depth 
of 820 feet, the latter a depth of 780; the former is a white water 
carrying 14.6 grains of total solids per imperial gallon, 50 percent of 
which is silicic acid; the latter is a brown water carrying 104.3 grains 
of total solids, of which only 4.2 percent is silicic acid and approxi¬ 
mately 90.0 percent is sodic carbonate. In 1896 I examined the water 
of a well 8 miles north of Alamosa, on what is given as the probable 
limit of the brown waters, and found that it carried 103.6 grains of 
total solids, almost 90.0 percent of which was sodic carbonate, with 
only about 0.33 percent of silicic acid. It is a question how waters of 
such different characteristics can occur in the same aquifers without 
any barriers caused by foldings or faults. These differences are found 
in all of the flows within these respective areas. The limits of the 
brown waters are not necessarily the limits of the alkaline water for 
the last water mentioned was scarcely colored at all. The limits of 
the alkaline waters have not been determined, neither has there ever 
been any attempt, so far as I know, to trace the alkalinity of the waters 
between the two sections to determine whether there is a compara¬ 
tively sharp line of separation or no line at all. The amounts of solids 
held in solution might be used as a criterion but this has not been at¬ 
tempted to my knowledge. In other words, the line between the acid 
and alkaline waters has not been determined. It is difficult to conceive 
how such lines can continue to exist, for even within the aquifers 
themselves there must be some diffusion, especially when so many 
openings have been made, which must establish some movement of 
these waters. A single 2- or 6-inch vent might not be of much sig¬ 
nificance, but when thousands of vents—upwards of 5,000—even if 
they are not .greater than 2 inches in diameter are furnished, one would 
expect a considerable aggregate movement within these aquifers which 
might tend to bring about a mingling of these waters and to eliminate 
any sharp boundary. No observations at all have been established on 
these points so far as I know and it is wholly unknown whether the 
limits of the alkali water may have changed during the past 20 or 
more years. This period of time is not too long, for there were as 
many as 2,000 wells estimated to have been put down by 1891. 
