1900 



S. S. BUCKMAN — EXCURSION NOTES 



177 



which become greater as the river impinges more, first on 

 the one bank and then on the other. In these figures 

 A A' are the sides of the valley, B is the curving stream, 

 and C C are the " spurs " of the convex portions of the 

 valley. These spurs tend to become more and more 



B A 



Fig. 6 



iNiriATiNG Curves. 



A' 



Hg. 7 

 Pronounced Curves .^nd 

 well-developed spurs. 



Considerable Meanders with 

 tendency to obliterate spurs 



worn away with the development of the meanders, on 

 account of lateral encroachment of the stream — encroach- 

 ment, that is, on the sides of the spurs ; and it is the up- 

 stream sides of the spurs which are most worn away. 



A' 



Fig. 9 

 The Meander Neck severed. 



In time, when the curvature of the meanders becomes 

 very great, the river straightens its course by cutting 

 through the narrow neck of the meander at D, as shown 

 in Fig. 9. 



M2 



