Sealed orders
![Australian troops embarking in Queensland in 1914. After assembling at Thursday Island and Port Moresby, their sealed orders directed them to capture German New Guinea.[1][2]](/uploads/202502/09/StateLibQld_1_85744_First_troops_leaving_Townsville,_Queensland,_bound_for_Thursday_Island,_19144041.jpg)
Sealed orders are orders given to the commanding officer of a ship or squadron that are sealed up, which he is not allowed to open until he has proceeded a certain length into the high seas; an arrangement in order to ensure secrecy in a time of war.