[51] 



POND CULTURE. 



.17 



grates are not practical. It has happened that throuMli oxidation iron 

 grates became so obstructed that openings had to be forced witli stron-' 

 poles, during which operation some of the bars of the grate were gen^ 

 erally broken, and, to prevent the fish from escajKng, the holes iu^he 

 grates had to be stopped with iascines. Wherever iron grates have 

 been employed they are gradually being replaced by wooden "ones. 

 When stone ta])-honses were first built iron taps were fastened to 

 wooden poles, which, however, did not prove a practical arrangement, 

 because it frequently happened that the iron taps remained in the pipe' 

 and only the poles were drawn, which, of course, necessitated labori- 

 ous and expensive repairs. Although the stone tap-houses are liable 

 to cause peculiar difficulties, the pond culturist should not thereby be 

 discouraged, but he should endeavor to improve thes(i tap-houses in 

 every possible way, because, on the whole, they are far preferable to 

 the old and cumbersome wooden boxes."* 



E. — The grates. ■ 



, All the exits of a pond must be so arranged that the water can flow 



, off easily, without giving the lish any chance to escape. For this pur- 



,. pose grates are placed not only at all the exits, but also at the plac<5s 



I where the water enters the pond, for it is well-known that fish like to 



I go against the stream. 



i. Delius gives the following description of the grate : 



I " It is a wooden grating, the Ijars of which are placed vertically, aiul 



,j which is close enough to keep the fish from passing through) w'hile it 



offers an unobstructed passage to the water. The size of the spaces 

 j between the bars depends upon the size of the fish which are in the 

 pond. The following is the construction of the grate: On both sides 

 ^ot the ditch strong posts, a «, are driven in ; between these posts another 

 |tlitch^is^dug,jicross which beams, h e, are firmly laid; on the top of this 



I *Horak, Tcichwirllischaft, 1869. 



