Above are three versions of the Hohnerette blow accordion taken from a Spanish language Hohner catalog from the early 1900s. In addition to the models shown, Hohner also produced the 3B model which had no less than five brass horns. They made little difference to the sound, but they certainly looked impressive.
The Hohnerette was patented in both Germany and the US in 1908.
A Brief History of Mouth Blown Free Reed Instruments
What Is A Free Reed?
Origins Of The Free Reed
Eastern Free Reed Instruments
A Selective Discography Of Asian Free Reed Instruments
Western Free Reed Instruments
Bibliography