18 U.S.C. § 1724 : US Code - Section 1724: Postage on mail delivered by foreign vessels

Search 18 U.S.C. § 1724 : US Code - Section 1724: Postage on mail delivered by foreign vessels

Except as otherwise provided by treaty or convention the Postal
Service may require the transportation by any steamship of mail
between the United States and any foreign port at the compensation
fixed under authority of law. Upon refusal by the master or the
commander of such steamship or vessel to accept the mail, when
tendered by the Postal Service or its representative, the collector
or other officer of the port empowered to grant clearance, on
notice of the refusal aforesaid, shall withhold clearance, until
the collector or other officer of the port is informed by the
Postal Service or its representative that the master or commander
of the steamship or vessel has accepted the mail or that conveyance
by his steamship or vessel is no longer required by the Postal
Service.