MAPPING OF THE CRYSTALLINE SCHISTS 



Fig. 8. — Details of topography of Monument Mountain, near Stockbridge, Mass. 



blocks, though subdivided by faults and joints) are sometimes 

 grouped into hills — composite blocks — which are spaced over 

 the general surface much like the black squares of a checker 

 board. Fig. 1 1 exhibits about two-thirds of such a hill in a 

 series of the kind described. Fig. 2 is a detail taken from 

 another hill of the series. 



