204 MK. JTJKES-BROWNE AND PKOF. HAERISON 



on one side of it and all the exposures of Scotland rocks would lie 

 on the other side, making it very probable that the structure of the 

 Boscobelle and Grant's Bay area is continued to the north-west 

 below the covering coral-limestones. 



Fig. 1. — Section through Welsh Town and Grenade Hall. 



N.W. S.E. 



Near Welsh Grenade 



Alexandria. Town. Hall. 



[Distance : one mile and a half.] 



Vertical scale : 1600 feet = 1 inch. 



S. Scotland Beds. O. Oceanic Beds. C. Coral-rock. 



(c) Outliers. — Besides the tracts which have been indicated, de- 

 tached and outlying patches of the Oceanic Series cap some of the 

 lulls within the Scotland district (see Map, facing p. 202). The 

 largest and most conspicuous of these outliers is that which forms 

 Bissex Hill, its summit rising to 966 feet above the sea. The length 

 of this is about one mile, with an extreme width of three-quarters of 

 a mile ; the beds seen everywhere dip to the northward, and their 

 base descends from between 760 and 770 feet at the south-western 

 corner of the hill to about 380 feet at the northern end of the outlier, 

 giving a dip of about 6° to the north. 



Korth-east of Bissex Hill are three smaller outliers, evidently once 

 connected with the larger one ; north-west are two others at about 

 350 feet ; and east of its southern border are three others at eleva- 

 tions of between 500 and 600 feet. 



The physical conformation of the country makes it clear that this 

 group of outliers was originally connected with the Chimborazo 

 area, for the distance between them is only a mile and there is 

 still a complete connecting ridge from Melvin's Hill (below Chim- 

 borazo) to the foot of Bissex Hill. The road from one place to the 

 other is carried along this ridge, and the traveller looks down on 

 either side into valleys that are 300 to 400 feet deep ; consequently 

 no geologist can doubt that the isolation of Bissex Hill is due to the 

 removal of material from this watershed by the action of rain. 



Chalky Mount, to the north of Bissex and only half a mile from 

 the coast, consists mainly of hard Scotland Sandstones, but the cen- 

 tral hill (551 feet) has a capping of white Oceanic earth and there 

 are still smaller patches on the two minor peaks to the northward. 



The only other outlier that came under our notice is near Bosco- 

 belle, and is brought in by the same fault as that which carries the 

 Oceanic Beds down to the sea-level at Grant's Bay, but it is separated 

 from that area by a deep valley cut in the Scotland Sandstones. 



