A file of signals intelligence reports, messages, and correspondence issued by the Government Code and Cypher School and sent by the head ('C') of the Secret Intelligence Service (MI6) to the Prime Minister, Winston Churchill. This file includes the following correspondence: from the Code and Cypher School (CSS) to and from Washington, 5 telegrams about the service of signals intelligence to the Prime Minister (PM), from September 12-14; an analysis of the service, 2 sheets that are undated (Secret Intelligence Service [SIS] material on the backs is being checked with London, and is probably not releasable); from the French liaison mission in London to General de Gaulle, from M Benes on U.K.-U.S. negotiations with the Soviets, on September 7; from the Brazilian ambassador in London, describing the reaction to Italy's surrender and U.K.-U.S. relations with the Soviet Union, on September 9; from the Turkish chargé in Moscow, that the Allies are to hold a three-power conference in Cairo, on September 8; from the CSS to Washington, instructions about the signal intelligence service to the PM, on September 10-11; from the Japanese ambassador in Berlin, that the death of King Boris of Bulgaria is a blow to Hitler, on the German take-over in Denmark, and on German-Italian relations, from September 2; from the German Ministry of Foreign Affairs in Berlin to all stations, stating the unconditional surrender of Italy, that the Italian fleet is to be surrendered to the Allies, and that German forces are securing Italy, southern France and Dalmatia, on September 9; from the CSS to Washington, the signals intelligence service for the PM, on September 9; from the Japanese ambassador in Berlin, on a re-shuffle of personnel in the German Ministry of the Interior and an impending reorganisation of industrial production under Speer, on September 2; and from the Japanese ambassador in Rome, on Italy after the collapse of Fascism, on September 2.