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Mostyn Tompion

  • Object type

  • Museum number


  • Title (object)

    • Mostyn Tompion
  • Escapement

  • Description

    Year-going table clock; gilded-brass dial with matted centre; silvered chapter-ring and silver spandrels; blued steel hands, minute hand counterpoised; days of week and their corresponding planets shown in apertures; at top is a strike/silent crank. Spring-driven movement, going-train with verge escapement and short pendulum; striking-train with 'rack and snail'; quarter-repeating mechanism can be operated by pulling cord at either side of case; 'rise and fall' regulation operated by precision worm gearing mounted on finely engraved front plate; year duration achieved by use of trains of six wheels accommodated between two sets of plates and driven by massive barrels and great wheels; great, second and third wheels of both main trains are housed in the lower set of plates; remaining wheels, with exception of the going-train crown wheel (which is positioned between the fusees) are all housed in the upper set; drive to the motion work is through a 'floating' centre-wheel; movement is secured to a metal base-plate; case slides down onto the movement from above and is secured to the base-plate. Case of ebony veneered onto oak, mounts of silver and gilded brass; dome bears Royal coat-of-arms and Britannia with shield bearing combined crosses of St George and St Andrew; at corners are rose (England), thistle (Scotland) and lion and unicorn (Royal Supporters); other mounts include emblematic crossed sceptres with crown, military trophies and lion masks; female mask at centre of base is flanked by garlands; pendulum and signature on front-plate visible through glazed aperture in front of which is a repoussé screen centred by a wreath flanked by cherubs seated upon strapwork.


  • Producer name

  • Date

    • 1689
  • Production place

  • Materials

  • Technique

  • Dimensions

    • Height: 73.6 centimetres
    • Width: 34 centimetres
    • Depth: 24.5 centimetres
  • Inscriptions

      • Inscription Type

      • Inscription Content

        Tho Tompion London Fecit [front-plate]
      • Inscription Type

      • Inscription Content

        T Tompion Londini Fecit [plaque]
  • Curator's comments

    Text from 'Clocks', by David Thompson, London, 2004, pp.84-87.
    Thomas Tompion
    Year-going table clock with quarter repeat, 'The Mostyn'
    London, c. 1690
    Height 73.6 cm, width 34 cm, depth 24.5 cm
    When it comes to opulence there are few, if any, English-made spring-driven clocks which would surpass this magnificent tour de force by Thomas Tompion. In the late seventeenth century, English weight-driven year-going clocks were extremely rare, while spring-driven clocks of such long duration were non-existent. However, year-going spring clocks had been made in earlier times, and notable surviving examples are the silver-cased clock by Johann Sayler of Ulm made in about 1630 and the clock by Johannes Buschmann made in 1652 for Augustus, Duke of Braunschweig-Lüneburg-Wolfenbüttel. That is not to say that Tompion had any knowledge of these clocks.
    Tompion's year-going clock marks the pinnacle of his achievement as a practical clockmaker. To make a clock that will perform efficiently for such a long period on a single wind is a most demanding challenge for even the most accomplished of makers. To increase the duration of clocks, extra wheels have to be added in the going train and this necessitates an increase in the strength of the mainspring. The result is that, if the proportions of the wheels and pinions are not of the most elegant, and if the forms of the teeth are anything but perfect, then the power needed to drive the machine becomes prohibitive. It comes as no surprise, therefore, that the making of such clocks was limited to a tiny number of craftsmen and that Thomas Tompion was the first in England to meet the challenge.
    The year-duration going train consists of a fusee and great wheel which drives a six-wheel train terminating with a verge escapement of very small proportions, controlled by a short bob pendulum with spring suspension and a rise and fall mechanism.
    The striking train is similarly extensive and here Tompion meets another daunting challenge. The striking train of an ordinary eight-day clock strikes 156 blows on the bell in a twenty-four-hour period or 1,092 blows in seven days. Tompion's year clock, therefore, has to strike the bell 56,940 times. In reality this clock runs for thirteen months and Tompion has even provided extra capacity so that the striking train can, be used as part of the quarter-repeat system as well which means that the clock can actually strike over 60,000 times on a single wind.
    The trains for the going and striking as far as the third wheels are mounted between massive lower plates, and the smaller and lighter components of the trains as well as the pull quarter-repeat mechanism are housed in the upper section. The pendulum swings in front of the movement and is regulated by a long blued-steel micrometer screw, turned by the capstan at its right-hand end. In the middle of the finely-matted dial centre, a sector aperture reveals a calendar giving the days of the week, each with a pictorial representation of its ruling deity.
    The ebony-veneered oak case is lavishly decorated with silver and gilt-brass mounts of the highest quality. On the front of the domed top is a crowned shield bearing the royal arms. The clock is surmounted by the figure of Britannia holding a spear and a shield which bears the combined crosses of St George and St Andrew. The gilt-brass masks and the silver garlands around the base emphasize the superlative quality of the mounts. This stupendous work by Tompion is thought to have been made in the coronation year of William and Mary. The royal arms that appear on the shield were used for only a few months during the sum¬mer of 1689 until the Scottish parliament agreed to recognize the joint monarchy, at which time a different version combining the Stuart arms with those of Nassau was used. The extremely high quality of all the mounts on the clock and the engraving of the front plate of the movement have provoked suggestions that the work must have been done by the best craftsmen of the time. The names Jean Berain and Jean Tijou have both been suggested as contributors to this magnificent piece.
    On the death of William III in 1702, the clock, which was kept in the Royal Bedchamber, passed as a perquisite to Henry Sydney, Earl of Romney, Gentleman of the Bedchamber and Groom of the Stole. Two years later, when he died, it was left to the Earl of Leicester and then passed by descent to Lord Mostyn, from whom it was purchased by the Museum in 1982.
    From 1793 the Mostyn family kept a written record of the clock's performance over each year, noting the names of those present at the annual winding ceremony. Although there are some gaps when the clock lay dormant or the record was not made, it does give an interesting insight into its performance. For instance, the record for 17 September 1884 reads: 'The clock was satisfactorily wound at 9.45pm by Robert Walpole Esq., L.E. Bligh Esq. and Lord and Lady Mostyn for the first time after their arrival at Mostyn Hall. It had not run down but had lost 2 hours'.
    Purchased 1982.

    Note:- thanks to research carried out by Lucy Wood at the Victoria & Albert Museum, it is now clear that the clock was part of the contents of King William's 'Little Bedchamber' and not the Royal State Bedchamber as given above.


  • Bibliography

    • Thompson 2004 pp.84-87 bibliographic details
  • Location

    On display: G39/dc9

  • Exhibition history

    Exhibited: 2004 10 Sep-29 Nov, Netherlands, Apeldoorn, Paleis Het Loo Nationaal Museum, The Pendulum Clock - From Invention to Perfection in the Seventeenth Century

  • Subjects

  • Associated names

  • Associated places

  • Acquisition name

  • Acquisition date


  • Department

    Britain, Europe and Prehistory

  • Registration number


COMPASS Title: 'The Mostyn', made by Thomas Tompion


COMPASS Title: 'The Mostyn', made by Thomas Tompion

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Object reference number: MCC3103

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