Diptych dial for latitude 40° North. Rectangular wooden dial faced with paper, consisting of two leaves that fold flat when not in use. Leaf Ia is blank. Leaf Ib features a vertical dial with the signs for Capricorn and Cancer marked at the top and bottom of the meridian line. Flowers in white and green appear below the dial and the leaf has a green border with red and blue inner edging. Leaf IIa has a compass with the hours for the horizontal dial set around it. The compass has eight points indicated by French initials, an arrow drawn to mark the magnetic variation at 20° West of North and a compass rose coloured in blue and red. The needle has an open ring to indicate North and is surmounted by a brass cylindrical pivot. There are floral motifs in the corners of the leaf and a green border with red and blue inner edging. The string gnomon is attached between the inner surfaces of the two leaves. Leaf IIb is blank. The leaves have brass hook fasteners and brass hooks for holding the dial open.

This dial appears to have been made by an amateur. The quality is poor, apart from the compass card, which may have been made by a professional maker. The compass card is French, but the latitude of the construction of the dial is too far south for use in France. The dial may have come from Italy or even Spain.

For more information regarding this dial please refer to the OUP & NMM catalogue, 'Sundials at Greenwich'.