i "< n ls 



them in their smxtmim outcrops on different tides of 

 these axes, succeed in deciphehng the geological structwe 

 of the area. 



4. Within the last few years much light has been shed 

 upon the structure and origin of schistose rocks. Evi- 

 dence has rapidly accumulated that these masses have 



FIG. r* BcfchlBii Co^fanM. Ttov* ik 8.W. of W 



b. 



been subjected to enormous pressure and extensive 

 deformation within the earth's crust The effects of the 

 severe stresses which have affected them, are specially 

 marked in those rocks wherein the original structure 

 can still be easily recognised. Among the schists, for 

 example, there sometimes occur pebbly tones or bands 

 of conglomerate, or even coarse boulder-beds. About 

 the original water-worn and sedimentary nature of these 



