The D&D Combination Tendency Barometer, Thermometer, Hygrometer, Stormglass, A53 combines all of the best features and is our top of the line - a true presentation piece. Functionally identical to any other DD Barometer tendency barometer, the beautiful mahogany stained wooden case with curved glass has an aluminum colored brass face plate, with a Storm Glass mounted beside the tendency barometer tubes, and a hygrometer mounted above the tubes. Mercury free barometer, similar to water barometers. It consists of two liquid filled tubes. One tube in a U-shaped which is open ended and filled with a red fluid; and one closed thermometer tube filled with a blue fluid, mounted parallel to each other. When the fluid levels are the same, the weather is changing. When the red fluid level is below the blue fluid level, the weather is fair. When the red fluid level is above the blue, stormy weather is predicted (low pressure allows the red fluid to move up the tube). The thermometer measures in both Celsius and Fahrenheit and the barometer measures in millibars/ hPa. The overall instrument measures 20 inches high by 6.7 inches wide and weighs 3 pounds. An absolutely beautiful presentation piece that will last for generations. Normally ships in 1-3 business days. MSRP: $278.00.