Diptych dial for latitude 48° North. Rectangular ivory dial consisting of two leaves that fold flat when not in use. Leaf Ia is a standard windrose (see related terms) except the directions are named in full in German and it is offset approximately 7° East of North. On leaf Ib is a plumb bob to ensure that the dial is level. On leaf IIa the compass is offset 7° East of North to allow for magnetic variation. The left hand side of the compass carries Lienhart Miller's makers mark - a fleur-de-lys. There is a single dial for Italian and Babylonian hours with a brass gnomon. There is a string gnomon for use with the two main dials attached between the inner surfaces of the two leaves. Leaf IIb features a standard lunar volvelle. The two leaves have brass horse-head fasteners, a single brass horse-head hook for holding the dial open, a brass clasp covering the slot for the wind vane in the side of the lower leaf and four brass bun feet.

The simple foliate decoration on the outer surfaces of this dial is one of two standard designs that Miller used on his dials (the other is illustrated on AST0476 and AST0380). The interior of the dial is also simply engraved. The plumb bob attached to the surface of leaf Ib is one of the few to survive on the NMM diptychs. Unusually, the compass rose on leaf Ia is offset for magnetic variation (that of Nuremberg at the time the dial was made). On leaf IIa, it is signed 'LIENHART MILER 1619'.

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