China. (Singapore). 1940. Air Mail envelope addressed to London bearing China SG 474, $2 brown and blue (pair) tied by Shanghai date stamp '21st June 40', endorsed 'By A.F./ Hanoi' with Saigon Central/ Cochinchina transit on reverse 'Juil 5', routed via Singapore with brown censor tape and 'Passed By Censor 16/ Singapore' cachet in violet on face and reverse.
This Air Mail cover is endorsed to go via Air France and Hanoi but the route via Hanoi ceased in July 1940 and so carried via Saigon and Singapore.