60 A RIVER OF NORWAY 



if one may believe the evidence of the oldest 

 inhabitant, is still continuing. 



The obstacle to be circumvented is an almost 

 sheer fall of fifty or fifty-five feet in height. 

 To mitigate the steepness of the ascent the 

 ladder takes a zig-zag course. The entrance 

 to it is directly from a natural shelf at the 

 bottom of the Fos, the water on which is at 

 high-tide level with the pool below. There 

 are in all sixteen steps, the leaps from one to 

 the other varying from three to four feet in 

 height. A few are rather rapids, up which 

 fish easily swim, than leaps. The little pools 

 are of different size and shape ; for the most 

 part the water in them is rough and foaming, 

 but some have more or less quiet backwaters 

 in which fish may rest awhile. At the top 

 is a strongly-built wall running upwards from 

 the head of the fall and high enough to keep 

 the river at highest flood out of the ladder ; 

 and through this fish-pass by one or other of 

 two hatches, used respectively in big and small 

 water, into the quiet and deep pool above. The 

 greater part of the ladder is blasted out of the 

 rock, the steps being built up with stonework 

 and baulks of timber; the whole presenting 



