Lot #453 WWII Censors: NORTHERN TERRITORY - DARWIN: 1941 (Sep 27) commercial cover airmail to Sydney then by sea to Connecticut with 'NAVY DEPARTMENT/Office of the US Naval Observer/Port Darwin NT Australia/OFFICIAL BUSINESS' cachet at U/L, very fine ' 7 /PASSED/ BY/CENSOR/ 2 'cachet in violet, minor blemishes. We have not previously seen the cachet: very interesting that the US Navy had a visible presence in Darwin at least 10 weeks before the attack on Pearl Harbor.