158 SEASON 1874-75. 



so as to ensure the plank bottom keeping always clean. If much 

 mud comes down with the water, some assistance must be given ; 

 but with ordinarily clean water no labour is required. 



The best mode of bringing the water into a plank pond is 

 undoubtedly by an aqueduct passing the end at a sufficient 

 height to allow two small spouts to feed the pond directly over 

 the end ; but at Howietoun, at the time when the first plank 

 pond was designed, the height could only be obtained at a greatly 

 increased cost. The first plank pond, therefore, had its inlet end 

 cut down a few inches, and the water was brought in through a 

 trough run past the end at about the same level as the top of the 

 pond. A cut in the side of the trough, nearly as long as the end 

 of the pond, led the water over a distributing-board, and to a 

 screen of wire-cloth (No. 16), fitted into the cut in the end and 

 sides of the pond. This screen was only 4 inches above the 

 surface of the water. It however was sufficient to spray the 

 water into a fine rain, thus aerating it thoroughly. A plank was 

 fitted across the low end of the cut, to strengthen the pond, and 

 also for the lids to close against. As the pond was in the open 

 air, some sort of protection against birds was necessary. This was 

 obtained by lids, consisting of a frame of wood as light as possible, 

 covered over with wire-netting, half inch mesh. And to give 

 shade for the fish when they wished it, the upmost lid was made 

 entirely of wood, light lining being used. This lid was hinged to 

 the cross plank above referred to, and a small piece fitted, closing 

 the plank to the inlet screen. 



On April 24th (1875) I find the following note : " There are 

 now 6400 pure Loch Leven trouts in the plank pond : 2400 being 

 from rearing-box 1, and 4000 from rearing-box 2. I find them 

 more difficult to feed than when in the rearing-box es." 



The plank pond was gravelled on the bottom for the first few 

 weeks, but I soon found disadvantages. Gravel held the dirt, got 

 foul, hid enemies, and made itself a general nuisance. The next 

 note of importance relating to the plank pond is May 1 5th : " 1 

 now find the fish in the plank pond easier to feed than those in 

 the rearing-boxes. About 20 have died in the plank pond since 



