REARING PONDS AND STREAMS. 



61 



A wide sole-plate is advised because it affords a 

 sort of dash board for the water, after it passes over 

 the dead-water board, and prevents the washing away 

 of the soil below the fall. Brick-bats, flints, or stones, 

 should be placed so as to prevent, as far as possible, 

 the wash of the fall, even if only of a few inches, as 

 the ceaseless flow of water has a wonderfully erosive 

 effect, more than the uninitiated would believe 

 possible. 



Sluices are to be set upright, and protected in 

 exactly the same manner, except that they must be 

 even more carefully guarded, as the fall is greater, as 

 well as the back-pressure, or pressure of water from 

 above ; so that there are two dangers to be averted in 

 their case. 



REARING STREAM SLUICES. 



