THE 



AMERICAN JOURNAL OF SCIENCE 



[FOURTH SERIES.] 



Art. XLII. — An Experimented Investigation into the Flow 

 of Rocks, by Frank D. Adams, assisted by Ernest G. 

 Coker. First Paper— The Flow of Marble. (With Plates 

 II-IY.) 



Contents. 



Introduction. 



Factors in Bock Flow. 



Results obtained in former investigation. 



Aims of present study. 

 Methods Employed. 

 The Floiv of Marble. 



1. Deformation of the dry rock at ordinary temperatures. - 



(a) At comparatively low pressures. Structure of the 



deformed marble. 

 (6) At very high pressures. Structure of the deformed 



marble. 



(c) Strength of the marble after deformation. 



(d) Influence of rest and of heat on the strength of the 



deformed marble. 



2. Deformation of the dry rock when at temperatures of 300° C, 



and 400° C. 

 (a) Strength of the marble after deformation. 



3. Deformation of the rock at temperature of 300° C. in the 



presence of water. 

 (a) Strength of the marble after deformation. 



4. Specific gravity of the rock after deformation. 

 Conclusions. 



Introduction. 



That the rocks of the earth's crust, under the stresses to 

 which they are subjected, have been bent and twisted in the 

 most complicated manner is a fact which was realized by the 

 earlier geologists, and it needs but a glance at an accurate geo- 

 logical section through any highly contorted district of the 

 earth's crust to see that during the folding of the rocks there 



Am. Jour. Sci.— Fourth Series, Vol. XXIX, No. 174.- June, 1910. 

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