This is an early twentieth century barometer. On the interior it is marked “RF”, surrounded by “Brevetés SCOG Paris” and has serial number 36152. On the exterior of the case is a brass plate marked “MAX KOHL | Werkslallen fur Prazislongmechanik | CHEMNITZ I.S.”
This is by Max Kohl a renowned maker of early scientific instruments. The barometer is housed in a wood and glass case with dovetail joinery.