Astronomical Equation Clock

An extraordinary English astronomical equation longcase clock signed Wm. Barker, Wigan, 1764. An exquisite work of horological craft combining astronomy, mathematics, history, complex calendar work, and ecclesiastical dates. The unique horseshoe shaped dial in the arch (a distinctive design feature of Barker), displays multiple complications. Features include:

Astronomical Dial:
Shutters rise and fall throughout the year to show the varying lengths of day and night
Time of sunrise/sunset and amplitude and declination of the sun
A revolving moon sphere shows the days elapsed of the moon phases and a 24-hour scale shows the time of high tide.

Equation of time (the difference between solar time (indicated on a sundial) and “mean” time, or the time on the clock. Solar and mean time coincide four times/year on irregular dates.

Calendar
Calendar indications include all of the Sundays in a given year, the weeks of Lent, and liturgical dates used to calculate Easter.

Dates of ecclesiastical and political events, such as Saints’ Days and the date of the execution of Charles I (his “martyrdom).

The clock has an interesting overlap of dates from both the “old” Julian and the “new” Gregorian calendar, which was adopted by the British Empire in 1752, and not yet fully embraced when this clock was made

While London continued to flourish, by 1740 areas of Northern England such as Liverpool, Warrington, Wigan and Manchester became respected clockmaking centers, particularly longcase clocks, as well as dial painters, etc. These clocks often reflect the sea port cities of their origin including tides, dials with sea scenes, etc.