ISOSTATIC THEORY 
103 
recently receives strong support from the mathematicians. Albeit 
so theoretical, mathematics is^ a mill which grinds exceeding fine. 
Yet, after all, what comes out of such mill depends very largely 
upon what is fed into it. So that, concerning earth problems, 
there is, perhaps, little to choose between rough guess of geologist 
and most pains-taking calculation of mathematician. 
In their critical bearing upon the foundations of isostasy the 
clues of mining, reinforced by the recent observations on the 
Basin Ranges and the Rocky Cordillera, seem to require that the 
mathematical equations be radically modified in order properly 
to satisfy the necessary consequences lately derived directly from 
the field, or else they will have to be given up as purely fictitious. 
But the mathematical hypothesis of isostasy of later years and 
the geological hypothesis of earlier years as upheld by Hershel, 
Dutton and Gilbert are in reality two very different postulates. 
The fallacy of Duttonian reasoning, as widely tested by practical 
mining operations and as carefully measured by geological calcula¬ 
tions, quickly turns the inquiry into other and more promising 
directions. When the prospects of the observational geologist 
and the closet mathematician became hopelessly confused it was 
discovered that there were under consideration two entirely distinct 
themes. One resolved itself into simple hydrostatics, and the other 
into impossible tectonics. Recognizing that the isostasy of Hay- 
forth and Bowie is not the isostasy of Dutton and Gilbert, both 
Becker and Davis, among others, ascribe the isostatic incongruities 
to tangential pressure and telluric crushing effect, which are of 
course not isostatic at all. 
Failure of Dutton’s hypothesis of isostasy to promote mine ex¬ 
ploration is in no sense discouragement concerning the aid which 
scientific principles> may give industrial activities. Isostasy when 
first formulated had no phase of ore search involved. Its exten¬ 
sion to the latter was merely a working guess. That it did not 
bring desired results merely forced the problems into other and 
allied channels for solution. From some one of these more 
promising and speedy achievements must ensue. 
Notwithstanding the fact that the isostatic hypothesis proves 
unavailing in mining its chief shortcoming points out a geological 
law that should be of great practical service in exploring for new 
mineral veins. The larger, or telluric, relations of dislocative 
fissure-veins seem capable of utilitarian direction. That fissure- 
