FOR PLEASURE AND PROFIT. 67 



manner, insist personally on proper attention being paid to 

 their working. It is an astounding fact that most attendants 

 are neglectful of screens and sluices, although in many cases 

 they are quite conversant with the enormous importance of 

 the proper working of them. 



In the chapter on natural and artificial redds I have referred 

 to the importance of using screens for protective purposes, ard 

 in dealing with the rearing of fry I have occasion to allude to 

 ths usefulness of specially screened portions of a stream or 

 specially fenced-off fry enclosures. The screens used for these 

 purposes need not necessarily extend the whole width of the 

 stream. Fig. 20 shows an elevation of an approved style of 

 screen for a fry enclosure, and the accompanying photographs 

 illustrate the application of the same to fry ponds and also to a 

 stream in which fry are being reared. The photographs were 

 taken at Mr. E. Valentine Corrie's fishery, and that gentle- 

 man was kind enough to remove some of the screens in order 

 to show how the fry are permitted to have the full range of 

 several fenced portions of ai brook as they advance in growth. 

 In other cases the screens remain in position. It will be 110^- 

 ticed that in each case the screens are fixed at an acute and 

 obtuse angle across the brook or at the outlet of the fry pond, 

 exactly after the same manner as that adopted for the big 

 river screen, and with exactly the same objects. In Fig. 20, 

 A A is a s tr or g frame work of wood covered with stout planking, 

 and B is the screen (which may also have a set of sluice boards 

 in front of it, if necessary, as in Figs. 17 and 18), and the 

 lines c c c c show the outline of the bank and be.d of the 

 stream. All the framework beyond this is buried in the bank 

 and in the bottom of the stream. Of course, the lines c c c c 

 may be extended as far as necessary on either side 

 and below, but the framework also should be proportion- 

 ately extended, as the secret of stability lies in this 

 penetrating well into the bed of the stream and the banks. 

 The screen apertures must be made to take screens of varying 

 perforations, and this remark, by-the-bye, may well be applied 

 to all framework for screens. 



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