A scarce Victorian horizontal magnetic sundial and pocket compass with paper dial in turned boxwood case after Samuel Porter c1850

Horizontal magnetic sundial and pocket compass having 1½” lacquered floating paper card with simple steel gnomon and brass pivot, and displaying hours. The decorative compass rose showing cardinals, intercardinals and false points, North marked by a fleur-de-lys, South showing a sun face.

Contained under a domed glass held within a turned boxwood case with push-fit lid, the inner lid with label displaying calculations to adjust to the correct time, the outer lid with simple turned decoration and carrying a motif of a moth. The verso of the case carrying a further label bearing instructions and headed “The Magnetic Time Indicator and Compass.”

Condition: The floating card clean, the compass swinging freely and finding north easily. The domed glass with minor marks, the case lid with a crack from edge to centre. The inner lid label with signs of ageing, the label to case verso worn.

Comments: This horizontal magnetic sundial design, a type of pantochronometer, was patented in 1824 by Samuel Porter, a prestigious scientific instrument maker and a member of a highly respected family of clockmakers.

A fascinating and practical instrument in good working condition, this magnetic sundial and pocket compass is a real collector’s piece.