CHAPTER XI 



On streams which flow as a series of roll-waves Observations 

 on a conduit from Territet to Glion Observations on the 

 conduit of the Griinnbach (Merlingen, Thunersee) Obser- 

 vations on the conduit of the Guntenbach (Gunten, 

 Thunersee). 



On Streams which flow as a Series of Roll-waves 



ON June 11, 1904, I walked from Grindelwald to 

 view the Apbach Waterfall. Alongside the sheet 

 of water which leaped from the overhanging part of 

 the rock was a small body of water sliding down 

 the precipitous, but not vertical, part of the rock. 

 The water here would have been only a small frac- 

 tion of an inch in depth if it had been uniformly 

 spread, but it was, on the contrary, flowing in 

 detached portions, having the form of small, wedge- 

 shaped, progressive " solitary " waves, miniature 

 bores, about J inch in amplitude, separated by 

 portions of rock which were covered by a film of 

 merely capillary thickness. 



The same phenomenon was seen on another occa- 



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