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at a height of some fifty feet above sea level, took a turn from its 

 south-easterly course to the north east, and joined the Danes stream 

 beyond Taddiford. The retreat of the sea-cliff would then have cut 

 into the stream at its most southerly bend. At once its lower course 

 must become dry, and its bed in the lapse of a century or two, aided 

 perhaps by agricultural operations, is to a great extent obliterated. 

 Meanwhile the Becton Brook terminates in a fifty foot cascade with 

 a lip of yielding clay. It is probable that the retreat of such a 

 cascade up a mile or so of valley could have been followed in one 

 lifetime. 



The cutting of a nearly perpendicular ravine becomes in such 

 circumstances almost inevitable. It remains for future generations 

 to see the demolition of the sharp cut little bunny and the rounding 

 of! of its edges into the gentler valley slopes above. The waters have 

 now practically lost all carrying power, so that the bed becomes 

 more and more obstructed by fallen debris. 



The whole of this phenomenon, which has now been followed 

 somewhat minutely, is removed from the usual process of inter- 

 river rivalry by the intervention of the sea. The old dry valley at 

 Longmead nevertheless affords a good instance on a small scale of 

 the kind of feature that may be sought for when a river head robbery 

 is suspected. In chalk and limestone districts dry valleys are often 

 referable to the collapse of underground channels. But a true river 

 formed valley of the largest or most insignificant type has usually 

 certain features — some out of many will usually be found remaining — 

 which serve to distinguish it. It will usually be of winding form ; 

 its base at least in the lower courses will probably be flat — marking 

 the old "flood-plain"; and especially it is likely to be found in 

 following a winding valley that the lower slopes of the sides im- 

 mediately above the flood-plain will be steep where their bend is 

 concave to the valley and gentler where convex. A very perfect 

 instance of this can be seen in the last two or three miles of the 

 Lymington River right down to and beyond its present tidal limit. 

 The steeper descent of Quay Hill at the foot of the steep High Street 

 of Lymington marks the last of the concave sweeps. This is well 

 below the present tidal limit, which formerly extended two miles 

 further up the river than at present. But this marked evidence of 

 purely river action clearly recalls the time when the Solent had no 

 tides at all at this point. It requires only a glance at the Beaulieu 

 river valley to be convinced of its purely fluviatile origin, and that 

 the salt water is merely an interloper within its wooded curves. 



The inference here is more obvious than at Lymington. But 

 when we pursue our way still further eastward down the old Solent 

 valley we must be struck by the varying character of its northern 

 affluents. Lymington and Beaulieu are at least comparable, but 

 what shall we say of the straight-cut Southampton water, to the 

 making of which the Test and the Itchen have mainly contributed ? 

 It is perhaps fair, having regard to its main direction and to what 

 we have already seen of its former magnitude now reduced by the 

 Avon, to consider the Test as the predominant partner in the 

 business of cutting this great waterway. However that may be its 



