That funny switch hanging over the side of the radio is a Barkelew switch. The antenna wire on the Radiola III had to be moved around to pick up different parts of the broadcast band. The Barkelew switch, an after market product, eliminated having to move the antenna wire around. With the switch all you had to do was adjust the two knobs to move up and down the BC band.
The switch was manufactured by Barkelew Electric Manufacturing Company, 1905 Columbia Avenue, Ohio. It was founded in 1904 when Charles S. Barkelew started the company. The Barkelew Electric Manufacturing Company manufactured switches and other electrical devices for industrial use.