234 SEASON 1877-78. 



tightly, and still easily removed. The west end of the pipe was 

 continued through below the centre pond's screen-box, to enable a 

 connection to be made with the catch-box of the west 130-feet 

 pond ; but owing to the pond being wanted in a hurry, this has 

 never been done, and the water which drips through the sluice- 

 boards has had to be (very inefficiently) kept out by means of clay 

 each time the pond required re-charring. The trouble and expense 

 this has entailed has shown me the great advantage and convenience 

 of the catch-boxes where properly drained. Fig. 159 is a section 

 of pipe, showing connections with catch-box and screen-box. 



The centre 130-feet was the first finished, being filled and 

 stocked with the S. levenensis hatched 1875 on the 4th July 1877. 

 The lead of the west 130-feet was concreted on its sides. The 

 course was an ogee from the screen-box to opposite the centre of 

 the pond. The moulds for the ogee were made and fixed on the 

 5th September, and the straight moulds for the sides of the duct 

 were completed the following week. The concrete was made of 

 the best Portland cement, whinstone road metal, and shivers of 

 freestone, mixed with sharp sand in the proportion of one of 

 cement to two of sand, and three of shivers and road metal mixed. 

 This has stood ten winters, and can be recommended as a cheap, 

 permanent, and safe revetement for the sides of water-courses. 

 A coping of double turf was laid on the top of the cement. After 

 the S. levenensis (hatched 1875) were transferred from the 60 -feet, 

 the pond was re-charred and the plank cope painted, and a larger 

 hole cut in the bottom to facilitate the pond being run dry. An 

 iron pipe was inserted below the bottom of the pond to the plug- 

 hole, to save lifting the flooring, and connected with the drain 

 from the hatching-house. 



The three 130-feets were emptied when required by a 6-inch 

 spigot and faucet pipe, passing from the old course of the burn 

 below the ponds, and communicating with each of them by 

 straight-eyes fitted into frames of heavy wood (white pine) on 

 which bronze plates were hinged as valves. These frames carried 

 perforated iron plates, so that large fish could not escape when 

 the valves were lifted. The perforated iron plates were counter- 



