The Lighthouse Tendency Barometer is mounted in an exquisitely crafted wood and curved glass case. There are two colorful images of lighthouses on this instrument. The top image is of the Portland Head Lighthouse in Portland, Maine. It is the classic lighthouse that everyone pictures in their minds eye whenever a lighthouse is mentioned. The image at the bottom of the instrument is the Montauk Point Lighthouse on Long Island, NY. It is one of the oldest active lighthouses in the US and was built in 1796 after being authorized by George Washington. Lighthouses are a sort of weather instrument unto themselves by aiding mariners in bad weather which makes them a natural for being featured on this Tendency Barometer which also has helped many mariners avoid weather problems for the past 175 years.
The Tendency Barometer was patented on December 23, 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 below the blue fluid level, the weather is fair (high pressure pushes the red fluid down in the tube).
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.
USA Orders Only (no international, APO and FPO orders, please).
This item can only ship GROUND SHIPPING. Do not choose Air shipping.
Generally leaves the warehouse in 1-2 business days.