1 September 1941
In regard to the points you were to note, from now on in case there is no special change, report once a week, but report each change of the following as they occur:
1. Arrival and departure of Houston.
2. Arrival and departure of more than 5 or 6 destroyers or submarines.
3. Arrival and departure of naval ships other than American; (report in detail the particulars and relationships involved).
JD 1: 5037 (H) Navy Trans. 9-11-41 (6-AR)
(EXHIBITS OF JOINT COMMITTEE , EXHIBIT NO. 2 JAPANESE MESSAGES CONCERNING MILITARY INSTALLATIONS, SHIP MOVEMENTS, ETC.)