Thunder glass with hardwood wall plate and brass drip tray. As far as we know the thunder glass is the oldest weather forecaster. Its origins are probably around 1619 in the southern Netherlands. The thunder glass, also called storm glass or weather glass, works exactly like a barometer on air pressure differences. The water rises in the spout at low air pressure (bad weather) and drops with high air pressure (nice weather). In case of an approaching storm, the glass can even overflow, resulting in ‘thunder in the glass’ (meaning: trouble is brewing). The overflowing water ends up in the brass tray. The thunder glass must be filled with (e.g. distilled coloured) water. Size base: 42 x 14 x 6.5 cm. Sizes glass: 24.5 x 9.5 x 9 cm. Will be carefully packaged and sent with track and trace.