Crane.|] Prospecting, Mining and Milling Machinerg. 239 
of which is shown in nearly all of the accompanying cuts of 
mills and in figure 36. 
The trough or launder is placed in the tops of support- 
ing bents which are spaced and braced by horizontal and 
diagonal timbers running from one to the other. The bents 
are placed from twelve to sixteen feet apart and are from 
25 to 60 feet in height, the height, however, depending 
upon the required height of the tailings elevator. Sufficient 
inclination or dip is given to the launder to allow the water 
readily to bear the tailings through it. 
FRONT SIDE 
Fig. 36. Bent for support of tailings launder. 
Often a tailings separator or unwatering device is placed 
in the launder to separate the water from the tailings, and 
so prevent the filling of the mill supply pond. The separa- 
tor often consists of a screen placed vertically, or nearly so, 
