NATURAL HISTORY OF BRITISH SALMONID^E. 129 



' A flood does not injure the ladder at all, but the winter's 

 ice would tear it away ; so, as it is easily taken down, it is then 

 taken away, and put so that the platform gets dried well by the 

 sun. The woodwork (k I) is left in its place as being out of 

 danger from ice. 



'The construction of the ladder, including wood, iron, and 

 labour, cost only 3/. at Kurczyn, and the cost of removal and 

 replacing, with any necessary repairs, about 12^. or 14^. The 

 ladder has only been used two autumns, and Herr Pietsch has 

 often had opportunities of seeing salmon ascending it without 

 difficulty. Before it was put up he had frequently noticed 

 numbers of salmon collected in the pools below the dam, and 

 making vain efforts to get over it, and at last getting caught by 

 the fishermen. But since the ladder has been in use the 

 salmon are rarely seen waiting in this way, as it enables them 

 to get up at once. Models of this ladder are in possession of 

 the Galician Fisheries Society, the Austrian Fisheries Society 

 in Vienna, and the German Fisheries Society in Berlin, and 

 drawings of it have been sent to England and America. As a 

 movable and cheap salmon ladder, it seems preferable to the 

 costly fixed affairs. With the necessary modifications required 

 by different conditions in dams and rivers, it offers exceptional 

 advantage, especially where expense is a consideration, and 

 there is not much water to play with.' 



Mr. R. B. Marston adds the following note : ' It seems to 

 me that we are much indebted to Herr Pietsch for inventing, 

 and to Dr. Nowicki for describing, such a very practical and 

 extremely cheap salmon ladder. It can hardly fail to succeed 

 if used on such rivers as the Don, in Aberdeenshire, at the 

 horrible weir at Armathwaite, on the Eden, at Totnes weir, on 

 the Dart, and other similar places where, except in heavy 

 waters, salmon cannot pass up stream.' 



Many rivers are absolutely blocked to the ascent of salmon 

 by impossible obstacles such as those referred to by Mr. 

 Marston, or by other barriers ; but where no such impediment 

 exists the instinct of the fish is to go on ascending by degrees 



I. K 



