THE CARP AND ITS CULTURE. 881 



again readily if needed, and must be provided with two or three-fold 

 grating's to prevent the escape of the fishes upon the opening of the 

 sluice. At the same time there should be an outlet-channel, several feet 

 in breadth, at the side of the pond, to allow the water to run off. This 

 must also be secured by grating, but should be kept open always, so 

 that in case of continued rainy weather or sudden and violent show- 

 ers of rain or thunder-storms no overflowing of the banks or dams 

 may be possible through the unexpected rising of the water in the pond. 

 Large fish ponds of several hundred acres extent (some have a surface 

 of 1,200, 1,500, or 2,000 acres) have generally and according to their size 

 two or three outlets 1 have described, and which pass underneath the 

 dam. The outflow from these is usually regulated by adj^ustment of the 

 flood-gates from the top of the dam. 



The so-called "Monche'- (monks) are wooden boxes, which stand in 

 the pond at a distance of a few feet from the dam. They are perforated 

 like a sieve, or are provided with small adjustable boards, and wooden 

 pipes run from them through the dam. In Bohemia they are called 

 •'carp-houses." They are, however, rarely used in large establishments 

 at present, only such culturists making use of them who have but small 

 breeding-ponds at their command and carry on culture on a small scale. 

 These locks suffer too much from the water, air and sun, as also from 

 the pressure of the ice in winter, so that they require considerable re- 

 pairs at an early date after their first coming into use; but they serve 

 their purpose fully in small ponds, especially in smaller ponds, which 

 are intended for pleasure or experiment. 



There are so many different ways of constructing these subterranean 

 sewers, that I may as well pass them over; they belong more particu- 

 larly to the department of hydraulics. It is the province of the cul- 

 turist to find for himself that which will be the best and most practical 

 method in the construction of outlets. 



If it be desired to make use of natural ponds, of which there are num- 

 bers in every State of the Union, it is necessary to ascertain whether they 

 can be put into the proper condition for regular culture. This can only 

 be done if the influx of water can be regulated and the entire drainage 

 of the pond made possible. An iutrenchment will be required with such 

 ponds in order to make them dry. Trunks of trees should be taken out 

 of them ; and where they are too deep they should be filled up, or, if 

 this cannot be done, they should be brought into connection with the 

 above-described sewers on the bottom of the pond. If this is not done 

 too many fishes will remain embedded in the mud when the pond is 

 being drained, and this lessens the profits to a great extent. 



Should any brooks fall into such ponds, as is often the case with large 



ones, they must be kept under strict observation on account of possible 



overflows which might occur. If it be practicable the brook had best 



be turned off and conducted alongside the pond, when the latter can be 



supplied with water if required. 

 56 



