50 THE BUILDING OF AN ISLAND. 



There is here, in fact, a fold in the strata. The rocks are hard beds of in- 

 durated clay, and towards the centre of the fold there are some slaty strata 

 with a very rough cleavage. The soil and debris of the road-bank hide the 

 junction of the two dips, but the slaty rocks at the two sides approach near to 

 each other. Nor is this change in the dip confined to the narrow space here 

 visible, for we find the layers lower down the hill dipping also E. by N. (at 

 about 45 degrees), and at Longford, at the foot of the hills, we find in the 

 road-trenches the rocky layers dipping at a high angle to E.N.E. It appears, 

 then, that at the spot where the change was noticed, we have passed from a 

 strip of country with dips within the southern quadrant into a strip of country 

 with dips within the northeast quadrant. If the rule which we found to 

 prevail in the Western Oblong can be applied to the Eastern Triangle, then 

 the boundary between these strips should lie about west-northwest and east- 

 southeast. 



Numerous observations along the shore and on either hand show this to 

 be the case, and enable us not only to mark down the northern limit of this 

 strip into which we have come, but also its southern limit. This southern 

 limit marks it off from the Waiter's Point district, in which we return to 

 southerly dips. 



Thus we have established that the key discovered to the arrangement of 

 the rocks in the Western Oblong is also the key to the arrangement in the 

 Eastern Triangle, at all events for its western part ; that is to say, the rocks 

 bere, as in the northwest, have been forced up into folds by great pressure from 

 about north-northeast. Bv following the same method of observing and map- 

 ping out the dips at various points we shall find that the arrangement prevails 

 throughout the Eastern Triangle. The different anticlinals and synclinals will 

 be found noted on the map prefixed to these pages, and those readers who wish 

 to follow out the details of the observations will find them entered in the ap- 

 pended Notes. 



The large folds of the rock layers which have been so far worked out 

 must be the principal, but considering that we cannot everywhere get access 

 to the rocks, and considering that we occasionally, though rarelv, meet with ex- 

 ceptional dips, it may be that other smaller folds occur. Contortions are not 

 uncommon, and it may well be that there are some small folds also. Fuller 

 observations of the rocks may discover these and thus make some modifica- 

 tions of the present results necessary. 



Contortions. 



Reference has been made above to "contortions" as being "not uncom- 

 mon " ; at the same time it must be noted that these twists in the strata are 

 not as frequent as we might suppose when we think of the immense pressure 

 there must have been on the rocks to force them up into the great ridges and 

 hollows which we have just studied. Examples of contortions may be seen at 

 the Fort in Christiansted, at Fort Augusta at the entrance to the harbour, and 



