Curiosity kills

After promising my my dear spouse that I would not buy any more accordions, this neglected Lachenal MacCann Duet (?) popped up on eBay and in the US. I bid really low since it's in such rough shape, but maybe it will make a nice project.

The bellows are completely deteriorated, but I can't tell much about the mechanism and condition of the wood, except that it seems to be hanging together with a roughly concertina-shaped geometry.

Concertina.com has a great page about the MacCann Duet configuration with samples of tutors and arrangements for the instrument (MacCann Duet Page). It seems to have been the dominant duet configuration in the later 1800s and first half of the 20th century. The Robert Gaskins article mentions that MacCann Duet 'tinas are increasingly rare because they are no longer being made. My thoughts are that this is because the demand is in decline and the new Hayden Duet system is now the preferred configuration. Here's another Gaskins article comparing the configurations.