APPENDIX A. 



In the following tables will be found the dimensions, etc., of locks and dams on 

 certain rivers and canals in the United States. 



ALLEGHENY RIVER, PA. 



(A) Upper and lower ends of both walls built of dimension Cleveland sandstone. 



(B) Lock has double floor; concrete at bottom of foundation and wooden floor above. 



(C) Culverts around quoins and six in each side wall; all closed by circular damper-valves. 



(D) Filled by six culverts in miter-wall, from cross-culvert, fed by two square damper-valves in upper 

 buttress, emptied by culverts around lower quoins; damper- valves. 



(E) Foundation of navigable pass. 



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