Ships Compass?

[Sealander]

Hello everybody,
another find is a bit of a mystery. From the water, a possible crash site of a RAF bomber (early WWII) emerged a compass in relative good shape.After many tears in sea water.

The inscription on the bottom: "" GEORGE FIELD & CO
50 or SO. HOLLOWAY HEAD BIRMINGHAM"

The size of the compass overall is 14 cm and 7,5 cm thick.which makes it very small for a ships compass. Besides the location in the river where it was found is not one where ships ran aground or get wrecked.
The condition of the compass is such that it has not been thrown away.
The maker George Field is not a renowned compass maker ( attemps to link the company to compass production failed, also at Birminham Library)
Qustion: who knows about this type of compass being used in RAF aircraft? German bombers had this type of magnetic compass in the tail with a repeater(s) in the cockpit, as far as possible from the magnetic disturbances by metal (engines etc)
Any comments?
Thanks
Sealander