How to obtain it. 177 



to remain, whether they like it or not ; but from the artificial bed 

 they can escape at any moment that they may be seized with a 

 desire to go. Indeed, perfect freedom is the secret of the whole 

 thing. The little fellows have no recollection of having been 

 shovelled about as eggs, and counted, and incubated on glass 

 grilles. They find themselves in a very natural and tidy-looking 

 place, and are content with their surroundings until a desire seizes 

 them to roam, and when this occurs they must find themselves at 

 perfect liberty to do so. 



In addition to the dug-out system and the wooden one, both 

 of which possess the advantage of being ready at very short notice, 

 excellent work of a more permanent nature may be done by using 

 concrete or brickwork. In this case, however, the work should 

 be done in June or July, and the water turned on a few months 

 so as to have everything well seasoned before hatching time. 

 Cement is partially soluble in water, but this only applies to the 

 time when water is first run over it. The soluble portions are 

 soon taken up, and the face of the concrete becomes coated with 

 a vegetable growth ; after this it does no harm. The great 

 advantages of these hatching beds are that they can be made 

 available for use at once ; that when once started no one has to 

 attend to them ; that they cost very little and do a great deal ; they 

 can be fitted up in a day, or a couple at most, on any stream, and 

 the results are certain if good eggs be laid down. It should always \ 

 be borne in mind that both ova and "alevins" should be keptj 

 well shaded from light. A box with a lid on is good, but the bed 

 made in an open ditch must also be covered. A few old boards 

 will come in very useful here. I have found larch slabs battened 

 together do admirably, look neat and rustic, and last for years. 



Only one thing more is needful for the successful working of 

 an artificial ova bed, and that is an unfailing supply of water. I 

 do not mean so much in the sense of quantity as in certainty. 

 There must be no doubt as to whether the supply will continue. 

 No choking of the screen or entrance of a frog into a tile must 

 be allowed to cause a stoppage of the works. These things are 

 easily guarded against, and proper precautions must be taken from 

 the first to prevent such calamities. A very simple way of dealing 

 with the water at the intake is to have a sufficiently large screen 



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