Physical description
Small hand held Scalebuoy in original box, screw on handle of black bakelite attached to a glass bulb containing liquid mercury
Inscriptions & markings
Tested and Guaranteed boston USA Pnt Applied For The Scalebuoy
Small hand held Scalebuoy in original box, screw on handle of black bakelite attached to a glass bulb containing liquid mercury
Tested and Guaranteed boston USA Pnt Applied For The Scalebuoy