CAKTER : THE EVOLUTION OF THE DON RIVER- SYSTEM. 395 
makes a rectangular bend to the S.W.. taking a bold semi- 
circular curve, then doubles on itself and comes round to Wortley 
in another great curve, where it receives a beck which flows 
northwards from Wliarncliffe Chase and bends round to enter the 
Don. After another marked loop the river receives another feeder 
from the Chase plateau also flowing northwards. These we may 
call A and B (Fig. 4), At Deepcar the Don receives the Little 
Don on its right bank. This I regard as a subsequent stream 
which has worked its way along the junction of the Millstone 
Grit and the Lower Coal Measures, which here bend round to 
the west, and, cutting back in the direction of Langsett. has 
captured the head-waters of the Penistone and Dunford branch 
of the Don. This view is supported hy the sudden change in 
the direction of the feeders of the Little Don at Langsett (Fig .2) ; 
and the existence of a flat col at the Flouch Inn, about a mile 
N.W. of Langsett, with a small stream flowing from each side 
of it, is also suggestive. These feeders, C and D. would on my 
theory be an obsequent stream (C) and a beheaded remnant 
(D). Returning to the Wharncliffe gorge (Fig. 4) we notice that 
from Deepcar southwards the Don cuts a straight channel through 
the Wharncliffe plateau, receiving two large feeders, the Ewden 
and the Loxley on its right bank, and flows in a S.S.E. direction 
to Sheffield. On the left bank at Oughtibridge it receives a 
couple of little streams which descend from the Chase through 
Wharncliffe Wood, and may be indicated by C and D (Fig. 4). 
That Wharncliffe Chase was the original watershed between 
Wortley and Oughtibridge seems to be indicated by the direction 
of these feeders. The streams C, D flow in the normal way of 
feeders of the Don, but A and B are quite abnormal, flowing 
north from the Chase as if they ran into a river draining north- 
wards, and then bending round in a most unnatural manner to 
flow into the Don, which there runs parallel to their upper reaches, 
but in the opposite direction. 
This northward flow of A and B I believe to have been the 
original direction of their course when there was a stream draining 
Wharncliffe Chase northwards, and that the bends they make to 
join the Don are the results of river capture, by which this flow has 
been reversed. Fig. 4 gives my suggestions for explaining these 
