Bui. 376, U. S. Dept. of Agriculture. 
Plate XII. 
Fig. 1.— Typical Outlet Structure. Will Partially Recover Velocity Head. 
Pipe is one-half diameter too high for inlet structure. Too much air would enter. 
Fig. 2.— View Taken from Structure in Figure 3. 
Hillside cut ravelings enter pipe and reduce capacity. A condition to be avoided. 
Fig. 3.— Entrance well Submerged, Reducing Amount of Air Carried into Pipe. 
