Astronomical Compendium
Square base with dialling quadrant on underside and compass on upperside within a protracting scale of degrees. Compass box has a compass and wind rose and an hour ring for a horizontal dial with a folding gnomon. On the same hinge is an equinoctial dial with a semicircular support for the hour ring and a notch for the gnomon and latitude quadrant (plumb bob missing). There is a lid fitting over the compass which has a nocturnal and zodiac-calendar-declination scale on the outer face and a lunar volvelle and calendrical tables on the inside. The nocturnal index also has sights and can be used for altitude measurement with the help of the suspension ring. Inscription: ". W . SNEEWINS . * . FECIT . DELFT ." on hour ring of horizontal dial and "1709" on tables of Easter dates and epacts inside lid. Height 118 mm width 118 mm. Material: brass. Inventory number 36000
Museum of the History of Science in Oxford GB, Lewis Evans Collection.