Has anyone ever "deciphered" a paragraph?

[Mark Knowles]

I don't know how I can reasonably discuss a private E-mail based on non-disclosable images here.

You have examples of encrypted texts using diplomatic ciphers, so it is just a matter of sitting down and doing the entropy calculation. That should be more useful than just philosophising about it.

It is unfortunate that it is not easy for me to publish copies of documents that I have received from archives without permission. If/when I write a paper on the subject I will get permission for those documents that I wish to include in that paper, but getting permission for all the documents/books that I possess seems too big of a task.

Generally my impression is that when people publish things on the Ninja forum they are images from documents already freely available online. My research relies mainly on books, which are often subject to copyright, or photoreproductions that I have directly requested from archives. There are some documents freely available online that I rely on, but a lot are not. I have had to seek out books or archival documents in order to progress my research as the materials available online are certainly not sufficient.

In the case of the generated cipher key that I referred to I don't yet have the original letters from which those cipher keys were derived. I intend to get copies of them, although obtaining copies of enciphered letters from archives tends to be harder than obtaining cipher keys. Cipher keys, including generated cipher keys, tend to be kept together in one folder in an archive. However enciphered letters tend to be kept mixed in with other letters, so locating enciphered letters in a archive is difficult.

This assumption that one diplomatic cipher is the same as another and therefore that the properties of one enciphered text are the same as another is a big mistake and it should be obvious that this is the not case.

More to follow...