Further to the call for help to decode a letter from John Armstrong (20 February 1808) for Madison Papers in a post last year, I made two updates in "An Outlier Code in Armstrong-Madison Correspondence (1808)" (marked "June 2026").
(1) The editors of Madison Papers found evidence suggesting that the letter was not intended for Madison. It is then no wonder that this could not be read with Madison's known ciphers or other State Department ciphers. I wonder whether Armstrong used any ciphers other than the known one with Madison, perhaps a private cipher with the ambassador in England or Spain that was not stored in the State Department office.
Even if the letter is not meant for Madison, the editorial team is still very interested in the content of the letter. If it can be solved in the next year or two, they could probably include it in their next volume of Madison Papers.
(2) This letter is interesting in that it consists of not only numerical codes but also what seems to be shorthand. In this regard, my original article only mentioned Taylor's shorthand did not match. Now I added names of other shorthands known at the time. (I thank Norbert Biermann for the info.) If the code is too tough, hopefully, the shorthand portion may provide a clue.
