58 How to obtain it. 



one third the size of hazel nuts, and one third the size of peas. 

 The two first may be mixed together and laid at the bottom, the 

 smaller stones forming an upper layer. Over this may be 

 scattered, so as to form just a covering, a very thin layer of 

 material, which may be described as fine gravel or very coarse 

 sand. Care must be taken, however, to keep out of the raceway 

 anything of the nature of fine sand. 



In width this raceway should be about three feet, and should 

 the natural gradient be too steep, a fall, or perhaps more than 

 one, should be made, so as to bring the part available for 

 spawning to a proper level. The best place for this fall is at the 

 leaf screen, if it can be so arranged, or at the point where the 

 water enters the pond. By making it at either of these places the 

 spawning race is not so much interfered with, but, of course, 

 much must depend upon the nature of the ground. This being 

 done the gravel should be put in. Then a series of very low 

 weirs should be made. They need not stand more than six 

 inches above the water level, but the depth of the water itself 

 in the reaches formed by these obstructions should run from six 

 inches to a foot. Whilst the raceway is being prepared the water 

 should be shut off so that the work may be properly carried out. 

 The reaches of water may be ten feet or ten yards in length, 

 according to circumstances. The divisions between each are 

 best made of stones or blocks of concrete. I have seen very 

 effective ones made by simply placing logs across the stream, and 

 where plenty are at hand and stones are scarce they do very well. 

 Having formed these miniature dams and made all right, the next 

 thing is to turn on the water and wait results. The effect of the 

 current will be to wash out holes below the weirs, and probably 

 to form a bank just beyond each of these holes. One great 

 advantage of having the water under control is now apparent, and 

 that is that the bottom of the raceway can be raked over, and the 

 gravel spread to suit circumstances. These banks may be raked 

 down, and the gravelly bottom otherwise improved, if found 

 desirable, by hollowing it out a little in the middle. When the 

 fish come up they will soon make short work of it, however, 

 rooting it up everywhere in making their nests. 



At the spawning time especially, as well as at other times, it 



