W. Preston Folding Ivorine Ruler R47

Original, quality late 19th century 24" folding ruler / measure in ivorine with nickel mounts. Each hinged joint has a mixture of steel bars and nickel bars and the steel ones have left some staining to the ivorine, otherwise all is in super condition. All the locating and locking pins are present and there are no twists or warping to the arms. One arm is detailed for the maker "W.Preston London". The calibration is basically in inches with many scales within that. Complete and in good and working order.