Antique barograph Qty 1

This is an old Negretti & Zamba (British) birdcage barograph that is housed within a metal and glass casing. Typically used in observatory, ship, port authority, industry, aviation and laboratory settings. This is not a desk model and it is rarer.

A barograph uses an aneroid barometer mechanism to move a pen over a rotating paper  covered drum creating a graph (barogram) of air pressure changes. A valuable tool for weather forecasting and analysis showing pressure trends. 1920s-1940s.

W44 x D19 x H29 cm.

Untested.