A very old compass of the manufacturer A.T. Ritchie from Boston. Serial number: This company was founded in 1850 by Edward Samuel Ritchie (1814 – 1895). One of the main innovative instruments maker in North America. He has made compasses for the U.S. Navy. I haven't been able to find out if this compass is also used, but that could just be. For the further history of this company you can on Wikipedia. For a book of more than 100 years old it still looks very good. It still works excellent. The compass is in a gimbal ring. Lots of photos attached. The photos are part of the description. Dimensions compass Height 10 cm Width 21.5 cm Gimbal ring 25 cm Weight: 6,4 kg. Will be well packaged, and shipped by registered mail and insured, with track and trace code.