The printed matter (“Drukwerk”) cover shown here was mailed aboard the frigate Hr. Ms. ”Johan Maurits van Nassau” in January 1953. Its destination was Yokohama, Japan. The frigate was on assignment in Korean waters during the Korean War. Upon the frigate’s arrival on January 22, 1953 in Yokohama, Japan the letter was delivered to a post office. A Yokohama date cancel (22.1.53) and a “Paquebot” marker were applied.
Paquebot: Mail posted aboard vessels on the high seas may bear postage stamps of the country whose flag the vessel flies. On arrival at a port, an officer of the ship must give the mail to the post office of the foreign city. That post office must cancel the stamps and dispatch the items. If the stamps are foreign, the Post Office facility must use a special paquebot postmark or apply the word “PAQUEBOT” to the envelope in ink or with a rubber stamp.