English air-flow meter with rotating vane: "Airmeter N° 736". London Negretti & Zambra late 19th-early 20th c Lacquered brass (or anodised copper?), 6 x 5,8 cm, with 8-bladed aluminum fan, 6,7 cm, the weighted base marked "Lowne's silver medal air meter". Mahogany case with label "Correction for air meter N°. 736". Silvered dial raised on 3 turned brass pillars and graduated 0-100 Feet, with subsidiary dials for HDS', THDS', 10THDS', 100THDS', and MILLNS'. The label in the lid suggests to "add 30 per minute to the observed air meter".

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