232 Davis — Framework of the Earth. 



became at an early date more rigid than the rest of the 

 crust, and therefore the adjacent weaker belts suffered 

 crushing and deformation: but this tacitly implies a 

 comparatively uniform application of crushing forces ; 

 for if the forces were unequally applied, belts of yield- 

 ing might be developed in broad areas of uniform resist- 

 ance. Again the whole discussion of mountain chains 

 has been conducted under the postulate that dislocations 

 and deformations of the crust result from a diminution 

 of earth volume, and that they are all either radial or 

 tangential; yet while tangential movements are recog- 

 nized as including folding and overthrusting, radial 

 movements are taken to include only down- settlings or 

 subsidences, all vertical upheavals being excluded, except 

 those that result from tangential crushing. A striking 

 example of this narrow thesis is found early in the great 

 work, where Powell's interpretation of the Uinta moun- 

 tains as an anticlinal upheaval, between less upheaved 

 areas on either side, is reversed into an interpretation 

 of adjoining lateral areas as having been lowered by 

 wide-spread subsidence, while the intermediate anticlinal 

 mass of the Uinta s remained relatively fixed. 



Xothing better illustrates the ponderosity of Suess's 

 mind than the tenacity with which he held to this thesis 

 in spite of the enormous magnitude of the subsidences 

 that it involves. When the doctrine of no upheavals 

 is applied to an isolated mountain mass like the Harz, 

 the highlands of which exhibit forms, of moderate relief 

 eroded upon deformed structures, it has to be supposed 

 that, if the Harz stood still, subsidence must have lowered 

 not only the surrounding land area but also all the 

 oceans of the world and all the continents that did not 

 then emerge from the lowering oceans. This calls for an 

 enormous contraction of the earth. The isolation of every 

 other highland, large or small, that has been accom- 

 plished by the subsidence of the surrounding regions at 

 a date different from the dates of other isolating sub- 

 sidences, similarly involves a great, world-wide contrac- 

 tion. Surely the total diminution of earth volume thus 

 called for is so great that the more economical doctrine 

 of local upheavals should at least be given careful con- 

 sideration before it is rejected. Yet no sufficient con- 

 sideration of this open alternative is presented in Suess's 

 works. Instead, the doctrine of subsidence, as if repre- 



