Ship's Hull Tendency Barometer by Allivan Marketing

The Tendency Barometer was patented in 1818 by Alexander Adie. 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 to the left of blue fluid level, the weather is fair (high pressure pushes the red fluid down in the tube). When the red fluid level is to the right of the blue, stormy weather is predicted (low pressure allows the red fluid to move up the tube). Actual pressure readings in inches and millibars (hPa) can be taken and a weather forecast made by using the tendency slider parallel to and above the measuring tubes.

This Adie Tendency Barometer is mounted a sandblasted frosted glass frame. A sailing ship’s half hull, made of solid wood, is mounted below the measuring tubes to give the instrument a definite nautical decor flair. Appropriate for your home, boat or office and comes fully assembled and with a calibration kit for setting to local altitude.

Measures 15" W x 9" H and weighs about 3 lbs. Shipping weight is 5 lbs.

Note: This item only ships by UPS to the 48 continental US states. I am sorry but this item cannot be shipped to Hawaii, Alaska, Puerto Rico or Military bases.