FOR PLEASURE AND PROFIT. 59 



both ends of the trough, to draw off one-fifth of the quantity 

 of water passing over the screen, i.e., the perforated zinc 

 bottom of the trough. The remaining four-fifths of the water 

 is conducted by an extension of the trough to a. surplus water 

 channel, and carries with it all debris. The trough is fixed 

 level, but the channel from which it gets its water supply 

 should have a fall, and should for preference run at right 

 angles to the trough at the intake. This supply channel is not 

 shown in the illustration, nor is the extended end of the 

 trough leading to the surplus water channel. The lengths of 

 perforated zinc forming the false bottom are fixed on a cleat 

 fastened against the side of and all along the bottom 

 of the trough. The illustration is so perfectly clear and so 

 easily understood that a drawing of a section is quite un- 

 necessary. 



The horizontal box screen illustrated is made; from another 

 model by Herr S. Jaffe, and is in use at the Earl of Den- 

 bigh's fishery, Ysceifiog, North Wales; the outlet shelf is 

 in use at Col. distance's Weston Fishery, Norwich ; the over- 

 head horizontal box screen at Mr. Edgar V. Corrie's Itchen 

 River Trout Breeding Establishment, Winchester, Hants. 



A form of screen that is very much in favour with many fish- 

 culturists is known as the slanting screen, and it is generally 

 used in combination with an ordinary upright sluice. The 

 next photograph is a general view of the contrivance as in use 

 at Mr. H. H. Gray's Hyde End Fishery, Brimpton, Berks, 

 and Figs. 17 and 18 are a section and sectional plan of same. 

 Where one pond only is concerned, this contrivance*, by bsing 

 made sufficiently deep, can be used for emptying the pond 

 and for adjusting the height of the water without the assis- 

 tance of a controlling sluice. It is a useful sluice and screen to 

 use at D, in Fig. 2 and Fig. 3 (see chapter on Redds), and in 

 similar 1 positions. It is very simple, but needs putting up 

 strongly. The bottom, on line A B, in Fig. 17, must especially 

 be made sound or the water will work under the sluice. This 

 slanting screen and sluice may also be formed in a box after 

 a similar manner to the horizontal box screen, or the hori- 



