Negretti & Zambra - London. Brass 'Weather Forecaster' No. 25. 1915. 
Attractive and practical brass Weather Forecaster No. 25. The instrument comprises three independently rotating rings, enabling data on season, wind direction and barometer reading to be computed, revealing one of 62 possible forecasts. The inner disc engraved “Negretti & Zambra London” and “Patent 6276 1915”. Numbered “25” on verso; only the very earliest bear a sequential number. 1915. [Diameter 4.75in / 12cm] Negretti & Zambra were undoubtedly the leading meteorological instrument makers of the latter 19th Century and early 20th.