Reo. W. Lower Carter — On River Capture. 545 



-continues past Doncaster in a north-easterly direction to Tliorne, 

 where it bends northward towards the Aire. It has, however, been 

 artificially diverted by the Dutch River to the Ouse at Goole. 



The history of the present river course is presumed to have 

 commenced when the Pennine anticlinal rose from the Cretaceous 

 sea, and the original consequent streams commenced to run down 

 the dip-slope of the Chalk. Slack Beck (Broadstone Dyke), which 

 is diverted south-east at Ingberchworth by a tributary of the Don, 

 is considered to be the head-stream of the brook that runs by 

 Cawthorne, only a nari'ow dip in the watershed dividing them. 

 The Don at Penistone (700') faces a watershed of 700 feet, which 

 forms a dip between Hoyland Swaine (900') and Thurgoland 

 {810'). Immediately beyond this watershed are the head- waters 

 of the Dove, flowing eastward in direct continuation of the course 

 of the Don above Penistone. The Dove is thus considered to be 

 the beheaded remnant of the Don. The southerly bend of the 

 Don and the cutting of the Wharncliffe gorge are explained as 

 due to river capture by a feeder of the Sheaf. This Wharncliffe 

 stream, with a rapid fall to the Sheaf, was able to capture 

 successively the Loxley, the Ewden, and the Little Don, and then 

 the watershed at Wortley was attacked by a branch of this stream, 

 and on the other side by a feeder of the Don. As the watershed 

 was cut through, the Wharncliffe stream, by reason of its steeper 

 fall, captured the Wortley feeder of the Don and then the Don itself. 



(2) The Dearne. — At a very early date the Bretton stream must 

 have been captured by the Darton feeder of the Cawthorne stream, 

 as it flows straight at the Woolley Edge escarpment (527'), and 

 therefore must have been captured before the land was reduced to 

 this level. The Dearne flows eastwards, by Barnsley to Cudworth 

 Common, where it makes a rectangular bend southwards, and cutting 

 through the Upper Chevet Rock (225') at Darfield, enters the old 

 valley of the Dove (100'). This gorge at Darfield proves the 

 extension of the 225-foot contour eastwards, towards Hickleton, 

 forming the watershed between the Dearne and the Dove, and there 

 is an old river valley at Frickley (200') between Clayton and 

 Hickleton, which was probably the original course of the Dearne, 

 which flowed through Hampole gorge into the central plain. The 

 Darfield gorge is a case of river capture by a feeder of the Dove. 

 The Dove itself had probably been captured by the Sheaf at a period 

 before the present level of the Magnesian Limestone escarpment was 

 reached by denudation. 



(3) The Bother. — The original consequents of the Rother are Shire 

 Brook, the Moss, and the Staveley stream. The Shire and Moss 

 probably coalesced and formed the head-waters of the Ryton. The 

 two gorges (330') uniting at Kiveton are plainly traceable, and have 

 subsequently been used, in all probability, as a channel of glacial 

 overflow. The Moss must have captured the Staveley stream before 

 it was itself captured by the Rother. 



The whole inner Don system is thus explainable by a series of 

 river captures, due to the deep cutting of its valley by the Sheaf, 



