THE ROMANCE OF A RIVER 



i6r 



shire and Derbyshire. 

 The river is repre- 

 sented by a contin- 

 uous hne, while the 

 brot:en Hues, some- 

 times coincident with 

 the river and at 

 other times forming 

 loops on either side, 

 show the county 

 boundaries. 



These curious 

 anomalies simply re- 

 solve themselves into 

 a consideration of 

 the changes which the 

 rivers have undergone 

 since the boundaries 

 were established. An 

 interesting case occiu's 

 near London. North 

 Woolwich is in the County of Surrey. 

 and yet it is on the Essex side of 

 the Thames. These examples, and many 

 others which might be quoted from other 

 parts of the countr}', tend to confirm what 

 we discovered when dealing with our type 

 stream. Rivers are not mere dead features 

 on the face of the country, but active, 

 changing — living. 



A river in its upper reaches has usually 



Uttof^^efer 



Sccr/e I men =2 rnneZ 



THE RIVER DOVE AS COUNTY BOUNDARY. 

 Showing how the river has changed its course, 



21 



111-: CL KVKS OF THE WYE 



sufficient carrj'ing power to sweep its 

 course clear of the debris loosened by it- 

 self or by frost from its banks. Hence 

 the bed is on rock and clean from sand. 

 But in the plains, with diminished velocity, 

 it is incapable of carrying anything but 

 the finest mud in suspension, and the 

 coarser f)articles accumulate on its bed. 

 Then comes flood time, when a great 

 scouring takes place. The sand is swept 

 further down stream, or spread over ttie 

 surrounding country to form the " flood 

 plain." Finally the sea is reached, the 

 current is arrested, and it drops all its 

 burden. Should it enter the sea by a wide 

 estuary, the inrush of tidal waters twice 

 a day sweeps the debris brought down by 

 the river up and down stream with the 

 flood and ebb. As a rule, the velocity 

 of the ebbing tide is less than the flowing 

 tide, and more suspended material is 

 carried inwards than outwards. This 

 results in a gradual accumulation of sand, 

 and finally the estuary may be silted up. 

 At low water sandbanks are left high and 

 dry, and through these the current flows 

 in uncertain and tortuous channels. But 

 if the estuary narrows near its mouth, 

 the rush of water through the small 

 opening keeps an open waterway. 



The estuaries of the Mersey and the Dee 

 afford very striking contrasts. They open 

 into the same sea, they are subject to 

 verv similar tidal conditions ; but while 

 the Dee is V-shaped with the wide part of 



