AND CA.HORE SHINGLE EE.YCI1, CO. WEXFORD. 



37 



there are " countertides " in dif- 

 ferent places, the principal one 

 being off Beer Head, where the 

 tide revolves, the " flow " tide at 

 the same time running both to 

 the N.E. and to the \V., while 

 there is a " drain" to the 8.S.W. 

 From the soundings on the Ad- 

 miralty Charts very little can bo 

 learned concerning the travelling 

 of fragments in deep water : one 

 fragment on every square foot of 

 the bottom of the bay would pass 

 unnoticed, while one fragment on 

 every square yard would be more 

 than sufficient to supply the ma- 

 terials to keep up the Chesil 

 beach. 



9. Portland Bill, the headland 

 that bounds Lyme Bay on the 

 east, is the headland, down 

 stream (in regard to the " flow " 

 tide), nearest to Swanage, the 

 English end of the nodal or 

 hinge-line of the tide in the En- 

 glish Channel. 



10. At Portland Bill it is high 

 water (at full and change of 

 moon) at 7 o'clock. 



11. At Swanage is the least 

 "rise" of tide and the greatest 

 current in the English Channel. 

 The range is 5 feet. 



12. The current in the English 

 Channel from its Atlantic en- 

 trance (a line from the Scilly 

 Islands to Ushant Isle)* increases 



the beach to theS.W. and on the 

 back (south) of the Dogger bank 

 (the shoal off the mouth of the 

 lagoon called Wexford Harbour). 

 From the Dogger bank this 

 shingle drifts N.E. into deep 

 water, from which some pebbles 

 are cast up on the Black water 

 bank, along which they seem to 

 travel, some to be driven in shore 

 on the Cahore beach, while many 

 of them go northward past Cahore 

 Point, where they are found on 

 the different beaches. 



North of the Dogger bank, 

 between it and the Cahore beach, 

 the rock-fragments that fall from 

 the drift-cliffs (which in places 

 are composed of very stony ma- 

 terial) are sucked seawards by 

 the back wash, and few or none 

 travel along the beach : neither 

 are there any pieces of the Gree- 

 nore rocks to be found here- 

 abouts. 



9. Cahore Point, which bounds 

 Wexford Bay on the north, is 

 the headland, down stream (in 

 regard to the "flow" tide), near- 

 est to Courtown — the Irish end 

 of the nodal or hinge-line of the 

 tide in the Irish Sea. 



10. At Cahore Point it is high 

 water (at full and change of 

 moon) at 7 o'clock. 



11. At Courtown is the least 

 " rise " of tide and the greatest 

 current in the south portion of 

 the Irish Sea. The range is 

 2 feet. 



12. The current in the Irish 

 Sea from its Atlantic entrance 

 (a line from Cape Clear to the 

 Scilly Islands) * increases till it 



* In both cases the currents do not increase in regular progression from the 

 entrance, on account of the tide in places running more swiftly round head- 

 lands, also on- : account of the complications of tides due to the respective offset 

 bays— that of the Gulf of St. Malo off the English Channel, and that of the 

 Bristol Channel off the Irish Sea. 



