An unusual small pattern barograph with the four diaphragms set horizontally, set in a walnut case with glass panel to front and rear (which is cracked). A label on the inside of the case shows it was retailed by A. Schumann, Hindenburgwall 43, Dusseldorf. Serial number 969 with an eagle logo and initials HF to the brass base. A quantity of charts and ink will be included.
Barograph – Small Pattern A. Schumann, Dusseldorf Circa 1920