A superb quality drum Barograph dating from the early to mid 20th Century. The barograph is cased in oak on a stepped base. The clockwork eight-day movement is housed in the drum, fitted with a seven day chart which covers one rotation of the drum. The aneroid barometer mechanism is gilt brass and has 4 stacked vacuum capsules and uses a gate suspension for improved sensitivity. The recording nib is on the end of a long arm which moves to record the pressure as the drum rotates.
The case measures approximately 13" (33cm) long by 8" (20cm) wide and 6 1/2" (17cm) tall. The drum has a standard diameter of 4" (10cm).
It comes with a small number of recording charts and it has its original ink bottle recessed into the case. New ink and charts are both readily available to buy online.
The clockwork mechanism is in good working order and the drum rotates as it should. I have not referenced the pressure readings for accuracy but I have no reason to believe it shouldn't be in working order.
It is in excellent condition for its age and has clearly been very well looked after. There are small marks here and there commensurate with age but there is no damage to report and the wood has a nice aged patina.
