Some months ago, there was an inquiry about the serial numbers for Lachenal Maccann and Crane duet concertinas (I do not cite the posting, since I do not want to embarrass anybody). Someone suggested that the numbering  started with a single series for both Maccann and Crane duets, and later was split into separate series for Maccann and Crane instruments. The truth is just the opposite: It started with a single series for Maccanns (John Hill Maccann Patent No. 4752, 12 March 1884). When Cranes