Not really sure what this was used for. Looks like it may have had 2 thermometers, but is missing one. Very neat rare item. Please see all pics. If you have any questions, please don’t hesitate to ask.The item “HENRY J. GREEN INSTRUMENT BAROMETER, B’KLYN, N. Y. THERMOMETER T. & W. A. INC” is in sale since Sunday, May 03, 2015. This item is in the category “Antiques\Science & Medicine (Pre-1930)\Scientific Instruments\Barometers”. The seller is “rjs3147″ and is located in Kansas City, Missouri. This item can be shipped to United States.