Submission from Commodore Roger Keyes [Captain and Commodore in charge of the Submarine Service] to the Chief of the War Staff, Admiralty [Vice-Admiral Sir (Frederick) Doveton Sturdee], reporting results of submarine reconnaissance, particularly activities of German destroyer patrols north and south of Heligoland. Keyes suggests a "well- organised drive" by British submarines to disrupt the patrols. [Carbon copy].