Diptych dial

Diptych dial for 42°-54° North. Rectangular ivory dial consisting of two leaves that fold flat when not in use. Leaf Ia displays a standard windrose (see related terms) on which eight winds are named in Italian. On leaf Ib the dial at the top of the leaf is numbered for night and daylight hours; Italian hours in red, Babylonian hours in green. Below the dial is a village scene with a castle. Holes for the string gnomon are numbered 42, 45, 48, 51 and 54. Below is a table of latitudes for European towns. There is no vertical dial.

Leaf IIa is as standard except there are five concentric hour scales for the horizontal dial. A black string gnomon is attached between the inner surfaces of the two leaves and is adjustable for various latitudes. The compass has a replaced paper card with Latin cardinal points and the magnetic variation is marked at 11° West of North. The Southern part of the leaf carries a scaphe dial for Italian and Babylonian hours with a brass gnomon. Leaf IIb features a standard lunar volvelle except the brass disc is missing. Miller's makers mark - a fleur-de-lys - with Miller's initials, appears twice at the hinge end. The leaves have brass hook fasteners, two brass hooks for holding the dial open and there are four brass bun feet on leaf IIb.

This dial is very similar to AST0476, particularly in the type of decoration employed. The gold leaf used to highlight the decoration still survives on the sunface on leaf Ib. On leaf IIa, the dial is signed 'LEONHART MILLER 1638'.

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

Object Details

ID: AST0380
Collection: Astronomical and navigational instruments
Type: Diptych dial
Display location: Not on display
Creator: Miller, Lienhart
Date made: 1638
Credit: National Maritime Museum, Greenwich, London, Caird Collection
Measurements: Overall: 13.5 x 71 x 100 mm