English, dated 1941 (from records), the base plate engraved 'Reynolds Son & Wardale Ltd, London' and engraved 'MO No.3871/41' constructed of polished wood, with lacquered brass baseplate holding 8 bellow stack arm mechanism, with clockwork drum, case with drawer to base and handle to top, case width 32cm.

Footnote: from the records at the Royal Navy museum this barograph was used in 1941 aboard ships. the readings then radioed back to shore.