Dutch ivory travel sundial with compass and calendar
On application
Dutch ivory travel and pocket sundial with compass and lunar calendar. With initials: M/MV.
2nd half of the 17th century.
The horizontal, IIII – XII – VIII numbered silvered brass scale of the sundial has a folding gnomon for the fixed latitude of 52 degrees. The sundial is placed above a compass with a coloured compass rose of printed paper. The whole thing is contained in an ivory cylinder-shaped box with a lid. In the lid is an engraved brass lunar calendar, which is used to convert lunar time read on the sundial into solar time. The moon calendar has three scales. The inner scale, on a rotating brass disc with pointer, runs from 4 to 12 and from 1 to 8 with Arabic numerals. The two outer scales are engraved on an underlying fixed brass disc. The first of these scales is numbered twice from 1 to 12 and the outer one from 0 to 29, where 1 corresponds to New Moon and 15 to Full Moon. Through a round opening in the middle disc, the moon phase can be seen.
Measurements: Diameter 4.5 cm. Height (closed) 1.8 cm.