Wednesday, April 20, 2011

Secret writing, 1917–1918

[“How to open sealed letter without detection.” Click for a larger view.]

From an April 19 CIA press release:
The Central Intelligence Agency today declassified the United States Government’s six oldest classified documents, dating from 1917 and 1918. These documents, which describe secret writing techniques and are housed at the National Archives, are believed to be the only remaining classified documents from the World War I era. Documents describing secret writing fall under the CIA’s purview to declassify.

“These documents remained classified for nearly a century until recent advancements in technology made it possible to release them,” CIA Director Leon E. Panetta said. “When historical information is no longer sensitive, we take seriously our responsibility to share it with the American people.”
The documents contain recipes for invisible ink and directions for opening sealed letters without detection. No sign of the documents at the CIA website, but they’re available from The Maddow Blog at MSNBC. I could’ve used them in my espionage-filled boyhood.

A related post
Invisible ink cigarette card

comments: 1

Anonymous said...

"The documents contain recipes for invisible ink..." How do you tell when you've run out of invisible ink?