T. S. Ellis — Windings of Rivers. Ill 



for its use. Here the case differs from that of the ' Oxbows ' on the 

 Mississippi. The short route has been abandoned ; the circuitous one 

 remains. Mortlake does not mean dead lake in the modern meaning 

 of the word ' lake,' but dead stream. 



The Thames also supplies striking instances, on a larger scale, of 

 river- windings, relics of old loopings. At Bray there is a tongue- 

 shaped area of low-lying land bounded, as it projects westward to 

 Waltham, by the 100 feet contour-line, so forming a shallow combe. 

 This, although now occupied by only a small stream, suggests an old 

 arm of the river between Bray and Sonning. Here again the river 

 goes, not "by the cord" — it has deserted that line — but "by the 

 bow " round by Henley and Marlow, receiving the streams which flow 

 down the slopes of the Chiltera Hills, representatives, it may be, of 

 larger ones at an earlier period. In my view, the river adopted for 

 itself the line of channel necessarily kept open by these streams, and 

 so the circuitous rather than the direct route became the permanent 

 course of the river. 



Only less manifest is the case of the Wey and Blackwater, separated 

 at a point between Farnham and Aldershot by a slight ' sill ' only. 

 The former stream flows in a direction down the line of the Thames to 

 Wey bridge, and the latter in a direction up the line of it to join the 

 Loddon in its course to the Thames near Shiplake. As I find, it is far 

 easier to believe that the two streams, so curiously close to each other, 

 were continuous when the river flowed at a higher level and occupied 

 a wider valley, than it is to imagine that the approximation signifies 

 a ' working ' or ' eating backwards,' going on towards ' capture ' of 

 one by the other, as similar features have been explained. Elbows in 

 two neighbouring streams pointed towards each other also suggest 

 a former union, and, generally, the level of the ground between them 

 does not forbid the supposition. An instance is seen in the Wey and 

 the Mole south of St. George's Hill by Weybridge, and, again, in the 

 Oak and the Childrey Brook by Abingdon. The Thames abounds, all 

 along its course, in interesting features illustrating the Natural- 

 history of rivers and, as I contend, showing the hopelessness of 

 attempting to explain river-windings by theories of reciprocal curves 

 or of relation between extent of curve and velocity or volume of 

 stream. 



On the other hand, appearances suggestive of old loopings as the 

 explanation of river-windings are very common. Ho one accustomed 

 to observe English rivers would be surprised to hear that Fig. 1 

 represented a mile or so in one of them. It really represents more 

 than 500 miles of the JSTile, and is taken from Dr. Budge's Guide to 

 Egypt and the Soudan. It shows, at the upper part, the meeting of 

 the Blue and White JSTile by Khartoum. In imagination I filled in 

 the lines so as to make a figure of 8, and then sought for evidence 

 of an old arm of the river to complete the lower loop. The little 

 upward curve at the foot is by Korosko at one end of a valley, 

 60 miles long, extending southwards up to Bab el (gate of) Korosko. 

 This, with other valleys, seems to afford sufficient evidence of an 

 old looping with the river at the prominence shown (Abu Hamed), 

 220 miles south from Korosko. 



