346 WAVES OF SAND AND SNOW 



flows, the separation of mud and water being too 

 slow. 



My observations of the ridges formed in 

 miniature deltas were made on the Bournemouth 

 cliffs between Canford Clifl"s, on the west, and 

 Southbourne, on the east. At the western end I 

 noticed chiefly the deposits, of which a photograph 

 is reproduced (Fig. 74), where during rains a tem- 

 porary stream had carried a large load of sand over 

 a steep and porous slope. The stream had appar- 

 ently been subject to rapid fluctuations of speed. 

 Whenever the speed slackened sand deposited at 

 the end, raising the bed and lowering the gradient ; 

 and presently the water subsided through this sand, 

 leaving it in a weald or ridge. Each succeeding 

 effort of the failing stream seemed to have ended 

 in a repetition of the process, but at a position 

 higher up, the final result being a long tongue of 

 sand transversely barred by wealds. I have not 

 had an opportunity of watching the process actually 

 at work in these tongues of sand quickly produced 

 during heavy rain, but the longitudinal sand-ridges, 

 prettily arranged like the fronds of seaweed, I have 

 often seen in actual formation. They are not found 

 on the western part of the Bournemouth cliffs, but 

 begin east of the Bournemouth pier and extend 

 beyond the Boscombe pier. They occur where 



