V-mail

V-mail, short for Victory Mail, was a hybrid mail process used by America during the Second World War as the primary and secure method to correspond with soldiers stationed abroad. To reduce the cost of transferring an original letter through the military postal system, a V-mail letter would be censored, copied to film, and printed back to paper upon arrival at its destination. The V-mail process is based on the earlier British Airgraph process.

V-mail correspondence was on small letter sheets, 17.8 cm by 23.2 cm (7 by 9 1/8 in.), that would go through mail censors before being photographed and transported as thumbnail-sized image in negative microfilm. Upon arrival to their destination, the negatives would be blown up to 60% of their original size 10.7 cm by 13.2 cm (4 ¼ in. by 5 3/16 in.) and printed.

According to the National Postal Museum, "V-mail ensured that thousands of tons of shipping space could be reserved for war materials. The 37 mail bags required to carry 150,000 one-page letters could be replaced by a single mail sack. The weight of that same amount of mail was reduced dramatically from 2,575 pounds to a mere 45." This saved considerable weight and bulk in a time in which both were hard to manage in a combat zone.

In addition to postal censorship, V-mail also deterred espionage communications by foiling the use of invisible ink, microdots, and microprinting, none of which would be reproduced in a photocopy.

The airgraph was invented in the 1930s by the Eastman Kodak Company in conjunction with Imperial Airways (now British Airways) and Pan-American Airways as a means of reducing the weight and bulk of mail carried by air. The airgraph forms, upon which the letter was written, were photographed and then sent as negatives on rolls of microfilm. A General Post Office (GPO) poster of the time claimed that 1,600 letters on film weighed just 5oz, while 1,600 ordinary letters weighed 50 lbs. At their destination, the negatives were printed on photographic paper and delivered as airgraph letters through the normal Royal Engineers (Postal Section) - also known as the Army Postal Services (APS) - systems.

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Wikipedia