FOR PLEASURE AND PROFIT. 



53 



the form of an elongated box, without ends or top, two boards 

 forming the sides and the third the bottom. The length of 

 these boards is one foot more than the deepest part of the 

 pond from B to H, Fig. 12, at which point the contrivance is 

 erected. At one end is formed a strong flange, J, which at 



Fig. 12. Sectional Elevation of Controlling Sluice. 



the front is wider than at the sides or back, in order to permit 

 of the sluice boards and screens falling on it when in posi- 

 tion. This flange is strengthened and more firmly attached 

 to the boards by means of the second flange, formed from 

 square wood, marked K. At the< othen end is fitted a, detach- 

 able cap, marked L, Fig. 12. Next the contrivance is fitted 

 with three long strips of wood on each side and inside. These 

 are marked M in Figs. 13 and 14, and their relative position 

 in Fig. 12 is shown by the upright dotted lines parallel with 



