Useful Exercise?

[Mark Knowles]

It is rather likely - but not certain - to be in the style of diplomatic ciphers of the time, that is a homophonic cipher (not a great term) with additional symbols for nulls, for letter pairs and for words (i.e. a nomenclator component).

I think the phrase "of the time" is quite an important one as there was quite a degree of change in the early 15th century. Diplomatic ciphers of the second half of the 15th century certainly fit that pattern. In Milan from 1446 that style seems evident. However it is unclear to me as yet when that became the standard amongst Milanese ciphers. This 1440 cipher and the 1444 cipher that I have shared elsewhere should both help to illuminate that. As I have, as yet, not located any Milanese ciphers from between the years 1425 and 1439 I can not say how Milanese ciphers evolved over those years, which is relevant as the 1424 Milanese cipher I have seen has some features not seen in later ciphers. I would be particularly interested in seeing Milanese ciphers from the period when Francesco Barbavara was Ducal Secretary and head of the Chancellery, that is the period 1425 to 1432.