Encrypted data?

[jlarmagost]

Apologies for multiple postings.

I'm looking at unpublished 19th century language materials written by a
non-academic in which the English glosses of certain common nouns and verbs
are encrypted by a simple substitution cipher. This appears to have been
done in order to spare the sensitivity of any English readers who happened
upon the materials without the author's permission, though there may be
other explanations.

I haven't seen this practice before and it strikes me as going well beyond,
for example, the use of initials, etc. to protect sources.

Does anyone know of similar cases, either within anthropology generally or
linguistic anthropology in particular?

Many thanks,

Jim Armagost