
On April 19, 2011, the Central Intelligence Agency declassified six secret documents from 1917 and 1918. These were America’s oldest classified documents and believed to be the last of their kind from World War I. So, what great secrets could possibly require nearly a century of security? Political intrigue? Government conspiracy? Something even worse?

One of the last Top Secret Documents from World War I
“Invisible Photography and Writing, Sympathetic Ink, etc.”
Source: CIA
Secret Documents…from World War I?
Not in the least bit. According to the official press release, the secret documents, which you can find here, “describe secret writing techniques.” Or, to put it more plainly, they describe how to create invisible ink as well as “a method for opening sealed letters without detection.”
Have you ever wanted to secretly open an envelope, World War I-style? Well, here’s your opportunity.
“Mix 5 drams copper acetol arsenate. 3 ounces acetone and add 1 pint amyl alcohol (fusil-oil). Heat in water bath — steam rising will dissolve the sealing material of its mucilage, wax or oil.”
Oh, but don’t forget this part.
“Do not inhale fumes.”
Why all the Secrecy over Outdated Secret Documents?
I have to admit that the secret documents provide some interesting insights into the national security concerns of the time. One paper exposes Germany’s secret formula for invisible ink. Another one provides 50 ways for U.S. postal inspectors to detect invisible ink.
“The rule is to suspect or examine every possible thing. The war between the spy or forger and the expert is continually bringing out new methods.” ~ Theodore Kytka, Handwriting Expert
“These documents remained classified for nearly a century until recent advancements in technology made it possible to release them. When historical information is no longer sensitive, we take seriously our responsibility to share it with the American people.” ~ Leon E. Panetta, CIA Director
Guerrilla Explorer’s Analysis
One of the secret documents revealed that America knew the secret to creating Germany’s invisible ink. I guess the German Empire will have to switch recipes going forward. Anyways, the CIA has long been considered one of the world’s most secretive organizations. From where I stand, the delayed release of these extremely outdated documents does nothing to change that reputation.
Well, I suppose we can be happy that these secret documents have finally been released. Now, we can move on to the next batch. What’s next on the list of oldest still-classified documents? Anyone?
Most likely. Published at all other documents. Who can prove?
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