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 reports on North Africa: of German Air Force (GAF) measures against a British landing at Tobruk; on the Mediterranean: that the GAF are to carry out increased recce operations to counter further British landings, on September 14; a GAF morning survey for September 14; 1406/T4 and 1406/T8 were returned to the Prime Minister (PM) under 737.