Attention Insider Trading Enthusiasts: "CIA recipe for invisible ink among newly released WWI-era documents"

You may have seen the wisdom in the Deal Journal post "Want to Get Away with Insider Trading? Try Snail Mail" a couple weeks ago but being security conscious as you are still had some doubts.
Here's the second ingredient for your retro approach to making a living on the edge.
From the Washington Post:

So you want to open sealed envelopes without getting caught?
Here’s the secret, according to one of the six oldest classified documents in possession of the Central Intelligence Agency:

“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.”

But there’s a warning for the intrepid spy: “Do not inhale fumes.”

Nearly a century after it was written, the recipe was released Tuesday by the CIA as part of a cache of six World War I-era documents. The documents, which deal mostly with invisible ink, date from 1917 and 1918 — predating the agency itself by decades.

“When historical information is no longer sensitive, we take seriously our responsibility to share it with the American people,” CIA Director Leon Panetta said in a statement announcing the release.
One document lists chemicals and techniques to create invisible ink for what is charmingly called “secret writing.” Another document, from June 1918 and written in French, provides the formula the Germans apparently used for their invisible writing during World War I.

All of the documents can be viewed at www.cia.gov in the site’s Freedom of Information Act Electronic Reading Room. They will also be available at the National Archives....MORE

 I don't think it was an accident that Secretary of State Stimson closed the State Department's code-breaking office just prior to the crash in '29 and tried to cover with his high-falutin' "Gentlemen don't read each other's mail".