788 THE JOURNAL OF GEOLOGY. 



ridge of Riga Schist is seen at A outlined from the surround- 

 ing Egremont Limestone by a dotted and dashed line. At 

 B and C are seen Turnip Rock and Barack M'Teth, composed 

 of Everett Schist. Between A and C the average strikes in the 

 limestones are nearly east-west, and the dips (due entirely to 

 pitch) about 30 south. Approaching Turnip Rock the strikes 

 become northerly and the dips easterly, as the limestone mantles 

 around the ridge A. 



A second elevated area of the Riga Schist having three 

 principal undulations in the direction of its prevailing strike, 



Fig. 2. Diagrams illustrating some of the structural features of the area studied. 

 Aj Flexures in crest-line of the western ridge of Riga Schist. B, Flexures in Tom's 

 Hill and region to the west (from section F, Plate VI). C, Diagram showing the cor- 

 rugated character of some of the smaller schist knolls near Salisbury. D, The same 

 in section. E, Diagram showing the probable manner of development of small steep 

 thrusts in the sharply folded region southeast of Tom's Hill, and in Horse and Peck's 

 Hills. 



corresponding with the three undulations of the western schist 

 anticlinal, is traced along the eastern margin of the district. The 

 northern of its three undulations brings to the surface in Peck's 

 Hill, schist areas 26 and 19, and the accessory overturned and 

 ruptured fold of areas 22-24 ; while the central undulation brings 

 up in Miles Hill and Tom's Hill schist areas I and 4, and the 

 southernmost undulation develops the extensive schist areas south 

 of Washining Lake (Area No. 6). The schist of Peck's Hill 

 disappears south of the swamp on the north base of the eleva- 

 tion, but the narrower eastern fold reappears north of the swamp 

 in Johnny's Mount and Barnard Mount, where it, too, soon disap- 



