1. GENERAL REQUIREMENTS 



W,WihHiM,MiMiWiW H, W , m i M ,M ,|-r1 , hrl i M i W i Wi 



Ex '40-1 60 



,W.M,M,M . k H, M i W ,>7l.M.U,W,MiW 





■ ^imiFTIiW^ikl.FTliFWiFWiFT^ 



'^ ■"'■*»<.-'': .£» "20-3.60 ■«* - 



&I-40-2-60 



Ek ^40-3 60 



NOTE: A owmaiwnt fnU 



number shall not be essJcned 



until hydrography is startad- 



Saal 13 



FlGURK 2. — Typical layout of hydioRiaphic survoy sheets showing field numbers. 



