This is a marine thermometer (aka 'bucket thermometer') for shipboard measurement of ocean temperature.  There are no maker's marks, the only inscription is "DWD 40/77".  DWD may be Deutscher Wetterdienst, the German weather service.  It appears to be identical to the marine thermometer made by the German firm Theodore Frederichs.  It has a mercury thermometer that ranges from -15C to 40C.  The thermometer is inscribed "No 307".  It's about 15 inches tall and weighs 7.6 pounds.

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