From: Tokyo (Togo)
To: Honolulu (Riyoji)
15 November 1941
As relations between Japan and the United States are most critical, make your "ships in harbor report" irregular, but at a rate of twice a week. Although you already are no doubt aware, please take extra care to maintain secrecy.
JD-1: 6991 25644 (Y) Navy Trans. 12-3-41 (S)
(EXHIBITS OF JOINT COMMITTEE , EXHIBIT NO. 2 JAPANESE MESSAGES CONCERNING MILITARY
INSTALLATIONS, SHIP MOVEMENTS, ETC.)