f24 SALMON AND TROUT. 



Total length from apex to base, including thickness of walls . 38 ft. 



Total width ,, ,, ,, ,, ,, . 9 ft. 



Length of watercourse inside walls 32 ft. 



Width of ,, ,, 5 ft. 



Length of spaces between steps of laJder, about . . . 5i ft. 



Width of side openings in steps . . . . . . 9 in. 



Width of central opening in top steps and at bottom . . 12 in. 



The model of this ladder, with some diminutive salmon and 

 trout fry to represent the ascending fish, was for some time ex- 

 hibited at the Home Office, and afterwards at the Horticultural 

 Gardens, South Kensington. A prettier sight it would be diffi- 

 cult to find, whether to the naturalist or the utilitarian. On 

 these little water steps it depends whether hundreds of thousands 

 of acres of waste river and sterile lake shall remain waste and 

 sterile or shall be converted into training nurseries for the pro- 

 duction of the most interesting, as well as the most valuable, of 

 all the great classes which were commanded to multiply and fill 

 4 the waters in the seas.' Certainly the little Salmonida took 

 kindly enough to the fish ladder even as babies and were always 

 on the look-out for the chance to go ' upstairs.' They might 

 be seen moving anxiously to and fro with their noses up stream 

 waiting for a start, and the moment the freshet came (the water, 

 that is, was turned on), up they went, jumping and racing like a 

 school of boys turned out for a half-holiday. The slope of the 

 ladder I am describing was one in five ; one in seven or eight 

 is, however, very preferable when circumstances will admit of 

 it, and, as I have stated, one in four is the maximum. This 

 ladder was intended to be built of masonry, but sometimes the 

 ladder is constructed out of the rock itself that is, all except 

 the steps. A portion of the side of the dam or fall is partitioned 

 off and intersected at considerable distances by transverse steps 

 of wood or stone, each intersection crossing about two thirds of 

 the whole width, and the fish are thus, 'step by step,' taken up 

 to a height of thirty or thirty-five feet, or higher if necessary. 



The longest fish pass or passage that has ever been attempted 

 was that made some twenty years ago by the proprietors of the 

 Gahvay fishery, in Ireland, between Loughs Corrib and Mask ; 



