286 WAVES OF SAND AND SNOW 



recall their appearance to the memory of many 

 readers if I mention particularly the rippled bed 

 of the Tiber at Rome and of the Arno at Florence. 

 At Innsbruck I saw them grouped in an interesting 

 way on a sandbank to leeward of a broad piejr 

 of the bridge. In this backwater the current 

 flowed towards the pier, and then, turning, 

 bifurcated and made its way to right and left 

 to the main streams on either side of the pier. 

 All these complicated currents were faithfully 

 recorded in the direction of the current-mark pf 

 the sands. 



In the Leven, in Lancashire, I saw current-mark 

 arranged in regular ridges at right angles to the 

 course of the river and extending from bank to 

 bank. The place was where the railway crosses 

 the tidal river on the way from Ulverston to 

 Windermere. I was myself a passenger in the train 

 and unable to reach the sands, but I judged the 

 wave-length of the current-mark to be about 

 9 inches. 



I am not able to establish by observation the 

 continuity between current-mark having a wave- 

 length of about 9 inches or i foot, which is com- 

 monly seen in clear, shallow streams, and the 

 larger sand-waves, which are generally unseen 

 during their growth owing to their situation or to 



