. SUCCESS WITH DUCKS. 187 



laying season is over, with suitable forage, fresh water, 

 security from marauders, and all other requisites, is com- 

 monly very difficult to obtain when the breeding birds 

 number not hundreds but thousands ; hence, the great 

 advantages of the outdoor exerciser for the ducks 

 reserved for breeding. 



All that is requisite is a distant row of feed cylinders, 

 as in Fig. 65, and in place of covered runways a row of 



FIG. 85. CRANK, WITH SET SCREW. 



long yards wide enough to admit a team for plowing, so 

 as to keep the soil free of taint, and at the nearby end of 

 the yards swimming tanks under the feed cylinders, as 

 in Fig. 86. In this figure, a ditch is cut and boarded at 

 sides and bottom ; c showing the original surface of the 

 ground, e an inclined plane of boards with lath tacked 

 onto afford foothold, and d, a .platform with a slight 

 slant for drainage. The feed cylinder is at A and the 



