Offered is an antique18 carat gold miniature barometer, altimeter, compass compendium. It is Hallmarked with the makers initials B&S, date letter Q, and 18. The outside diameter is 32.25-mm (1.25-inches). The spring hunter case opens by depressing the knurled knob. The knob is also used to rotate the altitude chapter ring. Back of case is monogrammed. The barometer movement was carefully removed from the case. One of the ball shaped nuts holding the movement in the case was loose and this is why the adjusting screw was askew and not lined up with the hole on the back of the case. When the movement was removed a series of hallmarks were observed under the movement. Photos will be attached to the listing. The adjusting screw is now accessible from the back of the case. When turned the needle does move. I also placed the barometer in a clear ziplock bag and applied a slight pressure; this also caused the needle to move. The item “Miniature Altimeter Barometer Compass Compendium 18 Carat Gold Hallmarked” is in sale since Wednesday, December 30, 2015. This item is in the category “Antiques\Science & Medicine (Pre-1930)\Scientific Instruments\Barometers”. The seller is “surcomp” and is located in Salem, Massachusetts. This item can be shipped to United States.