110 



T. S. EUi>i — Windinqs of Hirers. 



Black Forest. Here, having received a stream coming down from 

 Staufen, it has, in one case, settled into a single channel. The 

 partially effaced loops are seen on the opposite side as streams serving 

 to drain the local area. The river here does not form a sharp curve, it 

 inclines to its tributary, the two resembling the letter Y. The faint 

 upper stroke is, however, on the wrong side ; the figure should be 

 held up to the light and viewed from the back ; then the resemblance 

 is manifest. If the Rhine valley had been less wide and the country 

 on the margin less mountainous a single river might have sufficed. 

 Then it would have swung from side to side, taking in tributaries 

 on the convexities of great curves. The curved double lines in the 

 figure indicate an artificially regulated channel. The present condition 

 may be seen in the " Karten des Deutschen Keiches," pp. 630 and 

 643. I discussed the influence which a tributarj^ stream would have 

 in diverting the course of the larger one, supposing it to be straight, in 

 the Geological Magazine for Angust, 1903, pp. 350-354. 



Fig. 1. — Eiver-windings, a relic of an old figure-of-8 looping. 



That some relation exists between river-windings and tributary 

 streams seems to be indicated by such facts as the following : — On the 

 Thames, near London, are four well-marked windings near together. 

 Of these, three receive tributaries on their convexities : at Brentford, 

 the Brent ; at Hammersmith, the stream now only representisd for 

 a short distance bj- the creek ; at Wandsworth, the Wandle. The 

 convexity between Mortlake and Barnes receives no stream now, but 

 a very short channel cut in the alluvium would connect the river with 

 the Beverley brook which, directed due northward along the Combe 

 Valley, turns to the east and falls into the river opposite Fulham. 

 Assuming an old arm of a loop to have been partially effaced, why 

 did the river prefer to "go by the bow " and not " by the cord" ? 

 Because the Hammersmith stream required a channel to be kept open 



