THE MASTERPIECE OF DELVART
The diagram shows the 18 dials of the clock and listed below are the indications given by each with
minimal notes as to their functions.
1. The passage of time in seconds.
2. The passage of time in hours and minutes on a basis of 24 hours.
3. The passage of time in hours on a oasis of 12 hours.
4. The day of the week.
5. The date of the month.
6. The month of the year with signs of the zodiac. The calendar is perpetual and corrects for the
non leap years that occur when the century is not divisible by 400.
7. The Mundane Era - the passage of time from a given starting point. In this case 4 disks revolving
at different rates and giving the following indications: The periods since the Creation, the Flood,
the First Olympiad, the Foundation of Rome. the Epoch of Nebuchadneza, the birth of Jesus Christ,
the Julian Period, the Correction for the Gregorian period, Les Années de Tures. The disks
revolving variously for periods of 10 years, 100 years, 1000 years and 10,000 years.
8. Age and phases of the moon with the length of the lunar year - 354.75 days - and the difference
between the length of the lunar and solar years.
9. The lunar or metonic cycle - a period of 19 years after which the the phases of the moon will reoccur
on the same dates as before.
10. The epact - the age of the moon on the first day of the year.
11. The Solar Cycle - a period of 28 years after which the the days of the week according to the
Julian calendar return to the same sequence as before. The Dominical letter - the letter that
signifies the date of the first Sunday of the year and allows for the ascertation of the day of the
week at any date. The train makes adjustments for the fact that following the Gregorian calendar,
there are 3 leap years missing every 400 years. The Golden Number - a cycle of 19 years related
to the phases of the moon.
12. The Cycle of Indiction. A period of 15 years with no astronomical significance, but used to
make various ecclesiastical calculations.
13. The time of Sunrise in hours and minutes.
14. The Declination - the angular distance of a celestial body in degrees;ie.the angle between said
body and the celestial equator.
15. The time of Sunset in hours and minutes.
16. A hand for the Julian calendar showing the normal and bissextile years. A hand for the Gregorian
Calendar. A hand for the Saros Cycle - a period of 18 years, 10.33 days after which the eclipses of
the sun and moon follow the same sequence. A fourth wheel, concentric with the others, carnes no
hand, and there is no indication on the dial, but it revolves in a period of 521 years, and it seems
probable that the maker had the original intention of showing the calculated eclipses for the period.
17. Indication of the mobile feasts, namely Easter, calculated for a period of 389 years between
1800 and 2200 A.D.
18. The motions of the planets and major asteroids (see details on following pages).
The dial indicating the relative motions of the planets also includes the orbits of several of the major
asteroids. They are as follows, reading from the centre outwards: Sun, Mercury, Venus, Earth, Moon,
Mars, Vesta (discovered 1807), Juno (discovered 1804), Ceres (discovered 1801), Pallas (discovered
1802), Jupiter, Saturn, Uranus, Neptune( shown as Le Verrier).
The planet Neptune was discovered in 1846 by the German astronomer, Galle, following the
predictions of the French scientist, Le Verrier, who had spent a number of year studying the
disturbances in the orbit of the planet Uranus. This is the first clock made to show the orbit of Neptune,
and the name is given as Le Verrier in honour of the discoverer, but was quickly changed to
Neptune, to comply with the long-held convention of naming the planets of the solar system after
persons from Roman mythology.