Jeffries Maccann Duet in General Concertina Discussion Posted October 22, 2016 Yes, very strange. The tongues are near perfect with just the usual traces of rust, but the frames look as if they have been in an acid bath! There is still just enough metal to keep working, but only just. The rest of the instrument is very dirty, and certain sections, presumably relating to the main keys used, are black with what looks and smells like soot. Are we looking at the instrument of a railwayman from the steam era? Very little rust though, and no sign of water ingress. Having removed the old jeffries looking bellows, which are dried up and cracking, I find that the serial numbers on the frames match the number on the reed pans, so the suggestion of a replacement by Jeffries at some point looks like a possibility.