DIASTROPHISM AND THE FORMATIVE PROCESSES. I 
INTRODUCTION 
T. C. CHAMBERLIN 
University of Chicago 
During the century or more throughout which a gaseous origin 
and an early molten state of the earth were accepted tenets a full 
system.of doctrines relative to the formative and deformative pro- 
cesses of the earth was elaborated. In the earlier portions of the 
period these were largely based on the hypothesis of a thin crust 
floating on a liquid substratum. Later in the period various views 
of partial solidity grew up and modified the older tenets or replaced 
them with others. In more recent times essentially complete solidity 
has eome into wider favor and been made the basis of more radical 
modifications. But these views of solidity were in the main 
derivatives from the original postulates of a gaseous origin merging 
into a molten state and they retained the presumptions appropriate 
to such earlier history. There thus ran through the whole system 
of tenets a thread of philosophy that shaped it in harmony with the 
initial assumptions. It is true that particular tenets were not 
always consistent with the system into which they were introduced, 
but this is only an inevitable incident. The solid earth of this 
philosophic lineage was usually of the type that holds rigidity to be 
but a function of viscosity. The tenets of formation and deforma- 
tion built upon it embraced a doctrine of flowage of a slow secular 
sort directed by the principles of liquid motion restrained by 
viscosity. The presumption that such slow motion would take 
place under any appreciable stress if given time enough was a 
common tenet held widely and firmly. Specific doctrines of defor- 
mation and of secular tidal effects were worked out with great labor 
and skill on the basis of a visco-solid and even a visco-rigid earth. 
The tenets thus based on a solid and even highly rigid earth rounded 
tLargely the results of studies pursued under the joint auspices of the Carnegie 
Institution of Washington and the University of Chicago. 
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