Navies were the first military forces to adopt the newly developed electric Arc lamp Searchlights (S/Ls) in the later 19th Century, to illuminate potential targets at night. Before the Bombardment of Alexandria in 1882, the Royal Navy force employed its searchlights to prove that Ahmed ‘Urabi's troops were strengthening the fortifications at night in defiance of the British ultimatum. Similarly, searchlights were also used to defend Ports against incursions by warships at night: in Britain this role became the responsibility of the fortress engineers and electrical engineers of the Royal Engineers (RE).