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LX. An Outline of Mr. Mellard Keade's Theory of the 

 Origin of Mountain-Ranges by Sedimentary Loading and 

 Cumulative Recurrent Expansion: in Answer to Recent 

 Criticisms. By T. Mellard Reade * 



Introduction. 



IT is now four years since the ' Origin of Mountain-Ranges ' 

 was written, and during that time it has heen subjected 

 to considerable criticism by many able men in various parts 

 of the Globe. I have purposely refrained hitherto from 

 answering any of the objectors to my theory, feeling that it 

 would be better to wait and weigh them. It appears to me 

 now that most of the criticisms primarily spring from an 

 imperfect realization of its principles, scope, and details. 



The misconceptions no doubt largely arise from the complex 

 nature of the problems and the difficulty of keeping the 

 various threads of the argument unravelled. Under these 

 circumstances, I have thought that the best reply I can make 

 is to restate in a shorter manner the various salient points of 

 my theory. Probably, if I had given the theory a name, and 

 properly christened my bantling before sending it forth in 

 the world to seek its fortunes, I might have been saved from 

 paternal difficulties. 



To prevent further misconceptions, I now name my theory 

 the " Origin of Mountain-Ranges by Sedimentary Loading 

 and Cumulative Recurrent Expansion." 



The outline here given is of the barest character, and for 

 illustrations, details, proofs, and quantitative calculations I 

 refer those who want to know more to the work itself, as also 

 for those portions which deal with other theories, and are of a 

 destructive rather than constructive nature. 



Condition of the Earth's Interior. 



The Earth a Solid Spheroid. 



The latest mathematical investigations go to prove that the 

 Earth, taken as a whole, is solid, having a rigidity between 

 that of glass and steel. The facts of physical geology are in 

 accord with this view ; for if the interior be wholly fluid, as 

 some few contend, or if the nucleus be solid and the exterior 

 shell solid with a zone of molten matter between, as others 

 assume, the explanations of the physical conformation of the 

 surface, its mountains and ocean-basins, become questions of 

 flotation only. 



The crust of the Earth would be like a sheet of ice. This 

 * Conmiunicated by the Author. 



