52 
DUTTON. 
the shrinking nucleus. The objection to this explanation is 
twofold: In the first place, we cannot, without resorting to 
violent assumptions, find in this process a sufficient amount 
of either linear or volume contraction to account for the effects 
attributed to it. In the second place, the distortions of the 
strata are not of the kind which could be produced by such 
a process. As regards the first objection I will confine my¬ 
self here to a mere reference to the very able analysis of the 
problem by Rev. Osmond Fisher. I see no satisfactory reply 
to his argument. As regards the second objection, which, if 
possible, is more cogent still, it may be remarked that the 
most striking features in the facts to be explained are the 
long, narrow tracts occupied by belts of plicated strata and 
the approximate parallelism of the axes of their folds. These 
call for the action of some great horizontal force thrusting in 
one direction. Take, for example, the Appalachian system, 
stretching from Maine to Georgia. Here is a great belt of 
parallel synclinals and anticlinals with a persistent trend, 
and no rational inquirer can doubt that they have been 
puckered up by some vast force acting horizontally in a 
northwest and southeast direction. Doubtless it is the most 
wonderful example of systematic plication in the world. But 
there are many others which indicate the operation of the 
same forces with the same broad characteristics. The par¬ 
ticular characteristic with which we are here concerned is 
that in each of these folded belts the horizontal force has 
acted wholly or almost wholly in one direction. But the 
forces which would arise from a collapsing crust would act 
in every direction equally. There would be no determinate 
direction. In short, the process could not form long, narrow 
belts of parallel folds. As I have no time to discuss the 
hypothesis further I dismiss it with the remark that it is 
quantitatively insufficient and qualitatively inapplicable. 
It is an explanation which explains nothing which we want 
to explain. 
In proposing another view of the problem we may first 
turn our attention to those obvious and universally conceded 
