Arthur Gemeinhardt trained in the family business (August Gemeinhardt und Sohne) in Markneukirchen, Germany. He later worked for several years in the Berlin shop of Emil Rittersahusen. AG emigrated to the US in 1908. He worked for a brief period for William S. Haynes. Around 1916 he set up shop in NYC where he worked for George Haynes and Selmer's US operation (started by Alexandre Selmer, who hired George Bundy to run the place).I see. I can't find any info on Arthur, but that is the name of the father of Kurt Gemeinhardt's father, founder of the Gemeinhardt company... Is that who we're talking about?
Around 1920 Arthur started hius own flute-making business. His brother Walter also had an instrument making outfit in NYC. Kurt Gemeinhardt, founder of the now famous firm in Elkhart was Walter's son, Arthurs nephew.
Arthur's flutes are scarce and mostly sought after by collectors like me.