Alkalis In Colorado 
33 
a well known fact, one long since recognized, that the shales of several of 
the Cretaceous groups contain a remarkable amount of these salts, desig¬ 
nated by the general term “alkali”, including sodium, calcium and magnesium 
as sulfates, carbonates, and chlorids. 
“Analyses of incrustations from various parts of the State, and of 
waters from both ordinary and artesian wells, show the very general dis¬ 
tribution of these salts. They also corroborate the observation of their 
presence in the shales and other rocks which, whatever may have been the 
origin of the salts, serve at the present time to furnish the alkalis to the 
waters percolating through them. 
“The following figures, representing the general composition of the 
alkali, will serve to illustrate the general application of the assertion. An 
incrustation from the college farm showed: 
Calcic sulfate . 25.451 percent 
Magnesic sulfate . 19.798 percent 
Sodic sulfate . 41.748 percent 
The ground water from about 5 feet below the surface yielded an abund¬ 
ant residue, composed of 
Calcic sulfate . 35.648 percent 
Magnesic sulfate . 28.754 percent 
Sodic sulfate . 11.393 percent 
A surface well 28 feet deep yielded a large residue of which these 
salts formed 74 percent, as follows: 
Calcic sulfate . 15.206 percent 
Mag-nesic sulfate . 29.059 percent 
Sodic sulfate . 29.865 percent 
An artesian well, supposed to tap a water bearing Dakota sandstone 
and having a depth of 845 feet, furnished a water carrying 79 grains of total 
solids in each imperial gallon, of which 83 percent consisted of these salts 
as follows: 
Calcic sulfate . 12.036 percent 
Magnesic sulfate . 10.473 percent 
Sodic sulfate . 60.758 percent 
It is evident, not only from observation, but as is also indicated by such 
figures as these, that it is not at all necessary for the agriculturist to ques¬ 
tion in regard to the primary source of the salts included under the general 
term “alkali”. They are so abundantly present in the rocks and water, 
even in waters from considerable depths, that there is no need to seek 
further the source. The questions relative to another more remote origin 
and ihow it happens that the shales and even the sandstones are impregnated 
with these salts can be left to the geologist without serious inconvenience 
in studying the questions with which our agriculture has to deal. They are 
here, and in cases where the drainage of any larger area accumulates in a 
small basin, alkali salts will be brought together and, under proper con- 
