APPENDIX A. 



285 



MONONGAHELA RIVER, PA. 



* Locks and dams i to 7 were purchased by the United States in 1896 from the Monongahela River 

 Navigation Co. at a total cost of $2,210,000.00. Locks i to 4 are double. 



(A) Filled and emptied by wickets in gates. 



(B) Small lock filled and emptied by wickets in gates. Large lock filled by valves in floor of head-bay, 

 discharging under miter-sill; emptied by wickets in gates. 



(C) Filled by valves in floor of head-bay, discharging under miter-sill; emptied by wickets in gates. 



