Bull. U. S. B. F., 1929. (Doc. 1063.) 
Figure 6.— The lock as it appeared in course of construction. Looking upstream into the lock from below the lower gates 
which are swung back into recesses in the walls. The head wall and head gate are seen in the background 
Figure 7.— Setting a trammel net on the top of the lock gate to determine from which side the fish 
come 
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