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THE BOOK OF NATURE STUDY 



(Fig. 61). This will give the capturing stream more water, greater 

 velocity, and more eroding material. Thus its channel will be 

 further deepened, and its other tributaries stimulated until they too 

 capture the heads of other transverse streams and still more increase 

 the volume, importance, and power of the transverse stream to 

 which they flow (Fig. 62). The renewed power of the longitudinal 

 streams will enable them to cut back the scarp slopes overlooking 

 their valleys, and, as these retreat, the heads of dip streams rising 



FIG. 62. Second Stage of capture by the stronger stream. 



in them will be shortened and starved, and the rain water which 

 previously fed them will in turn drain to the captor. Thus, 

 little by little, the stronger streams will grow stronger and more 

 important, the smaller ones being one after the other diverted 

 and captured, or starved out, until the final result will be the 

 survival of two or three important rivers, each with a complex 

 set of tributaries, the majority of them being longitudinal, but 

 each of the latter fed by numerous small transverse head streams 

 which they have captured. The result of capturing may be 



