480 REPORT OF COMMISSIONER OF»FISH AND FISHERIES. [14] 



that can be used, and by the mauuer in which it is supplied, so as to 

 prevent a lack of water in dry summers. Ko fixed rules can be laid down 

 for this ; and it will always be advisable in the beginning to flood only 

 a comparatively small area by placing the bottom of the grates as low 

 as possible, and it will soon appear whether it will be necessary to flood 

 a larger area in order to obtain a suitable depth of water in the pond. 

 For the better understanding of the following, we will give here a 

 ground plan and elevation of a fish-pond, showing its different parts. 



aaaa, the pond ; &tt, tlccp place where tliefisb can go when the rest of the pond is drained— the Ash- 

 pit ; cccc, grates round the tap-house; f7, tap-house; cc, main ditch ; /f/', side ditches; y, deep place 

 wheie those fish are retained which escape through outlet pipes— the outer fish-pit ; h, outlet; i, 

 ditch tlu'ough which the water flows into the pond: Ik, ditcli lor supertluons water; I, grates; m, 

 weir ; o, dike : p. outlet pipe passing undevucatli tlio dike. 



