Some canceled etiquettes etc......
Cover from Dar es Salaam, East Africa. airmail etiquette has been canceled at Bombay on 27 OCT 34. Square strike.
Cover flow on the second experimental airmail to Gaza, Palestine. Note the airmail etiquette has been canceled with two red bars.
A registered cover from Mombasa to Cutch Mandvi (stamped on reverse) where the label is rubber stamped "BY AIRMAIL" in red. Postmark 30 MY 47.
1931 flight covers with different airmail etiquettes.