- Museum number
Year-going clock; frame of cast brass plates, hammer-hardened; fastened by five pillars riveted to back-plate and pinned to front-plate; train of five wheels, upper three supported in sub-frame with its three pillars riveted to back-plate; spring-operated maintaining power ('bolt-and-shutter') engaged by pulling small cord; when first set, driving weight and 13ft pendulum swinging once every two seconds, were suspended below the movement; later adapted for domestic use; escape-wheel with 60 teeth, made to drive conventional 39in pendulum, is modern replacement; original escapement based on dead-beat, later replaced.
intermediate wheel, 96
centre wheel 80
fourth wheel 48
escape wheel 30
Cannon pinion 30
Hour wheel 60
- Production date
- Curator's comments
Text from 'Clocks', by David Thompson, London, 2004, pp. 80-83.
In 1674, a committee which included Christopher Wren, Robert Hooke and the astronomer John Flamsteed, set up by Charles II to investigate claims that variations in magnetic dip could be used to determine the longitude of a particular place, was asked to look into claims by a Frenchman, the Sieur de St Pierre. Through the king's mistress, Louise de Kéroualle, the Sieur had proposed to Charles II that longitude could be found by observing the motions of the moon. In response, Charles charged the committee to investigate the practicality of the Sieur's claim.
This led in 1675 to a Royal Warrant enabling an observatory, designed by Sir Christopher Wren, to be built at Greenwich, and for John Flamsteed to be the first Astronomer Royal. The Warrant began 'whereas we have appointed our trusty and well-beloved John Flamsteed, master of arts, our astronomical observer, forthwith to apply himself to the rectifying the tables of the motions of the heavens, and the places of the fixed stars, so as to find out the so-much desired longitude of places for the perfecting of the art of navigation'. Sir Jonas Moore supervised the construction of the building and commissioned two specially-designed regulators from the leading London clockmaker of the time, Thomas Tompion, and a third from a Lancashire clockmaker, Richard Townley, whose dead-beat escapement, subsequently modified by Tompion, was used in the clocks.
Thomas Tompion was baptised on the 25th of July, 1639, in Northill, Bedfordshire and lived in the nearby hamlet of Ickwell Green. Nothing is known of his early career. In 1671, he can be traced in London where he established a business in Water Lane just off Fleet Street. In 1674, he supplied a turret clock for the Wardrobe Tower at the Tower of London and a quadrant for the Royal Society. The following year he made a watch for King Charles II. In 1675-6 he was commissioned to make the regulators for the new Greenwich Royal Observatory. Tompion became the most celebrated of all English clockmakers and established a business with a reputation second to none in Europe. He was admitted as a Free Brother in the Clockmakers' Company in 1671, was granted full freedom in 1647 and held the office of Master of the Company in 1703/4. He died in 1713 and was buried in Westminster Abbey.
Both of the Tompion clocks survive, one in the National Maritime Museum, the other in The British Museum, but the whereabouts of the Townley clock remain unknown. Astronomers had always been great campaigners for accurate clocks, essential to their work, and the clocks installed in the Greenwich Royal Observatory in 1676 were at the time the best in the world, enabling Flamsteed to record the motions of the planets and the moon and establish the true positions of the fixed stars.
The large square dials were velvet covered and while they seem at a glance to be of standard design, they are not so. The chapter ring is calibrated in hours I-XII, with an outer ring divided into minute divisions, all numbered and calibrated 1-60 twice, i.e. for a minute hand rotating once in two hours. The subsidiary dial above the centre is for seconds, divided to single seconds and also numbered 1-60 twice for a seconds hand revolving once every two minutes. Thus the time on the dial shown here is forty-four minutes past two o'clock and not twenty-two minutes past, as it first appears (see image no. AN32111). However, this clock was designed specifically for use by an astronomer who was not concerned with the time of day. Above the VI numeral a silver plate around the winding hole is inscribed, 'Sir Jonas Moore Caused this Movement With great Care to he thus made Ao 1676 by Tho Tompion'. At the top of the plate is the inscription 'Motus Annus' indicating that the clock will run for a whole year on a single wind. Even so, the massive movement is furnished with maintaining power to keep the clock running during winding. Clearly these clocks were never meant to stop from one year to the next. When the clock was set up in Greenwich it had a two-seconds beating pendulum measuring 13 feet (3.96 m) long. After initial adjustments made to the escapement, Flamsteed recorded that the clocks were keeping time to within two seconds per day.
Following Flamsteed's death in 1719 his widow removed the clocks and instruments from the observatory on the grounds that they had been the property of her late husband. At some time after this, this clock was converted to domestic use by the replacement of the escape wheel so that it would function with a seconds pendulum. Recently, however, with funds provided by the Townley Group of The British Museum Friends, a new dead-beat pin-wheel escapement has been made by Jeremy Evans, curator at the Museum. The escapement is based on surviving sketches of Richard Townley's original concept and the clock now performs as it used to, with the pendulum beating two seconds and swinging at right angles to the dial.
Purchased in 1928.
Information supplied by Jeremy Evans, former curator of Horology at the British Museum (May 2011)
Greenwich Year-Going Timepiece 1. 1676.
Originally installed into wainscoting of the Octagon Room, Greenwich. When this clock was offered at auction in 1923 it was housed in ‘an Empire mahogany tall case, 7ft 6in high’. Courtenay Ilbert is said to have described this case as ‘an ill proportioned red mahogany case [of the] so-called Regency period’, but no illustration is known to exist. It is possible that the case was retained by Webster – it is not believed to have accompanied the clock when it was acquired by The British Museum in 1928, and a new display case was provided.
17½” square, with four substantial feet, pinned, not latched, the front surface of the plate left roughly filed to enable a better bond for the glue which would have held the covering of material - possibly a fine velvet. This was probably sewn around the edges, but some of the holes at the edge of the dial are large enough to suggest it could have been held at the back by wooden battens – there is a shadow around the edge on the back side, but this could also have been caused by a new covering being folded over the edge and glued there. It is difficult to say, because there are two sizes of hole. Those away from the corners are certainly more likely to have been for stitching (they are as small – same drill? - as the unused pilot holes which were left in the back-plate), whilst those in the corners are larger. Perhaps it was glued, sewn and battened. The material would have been protected at the edges because the dial would have been pushed into its framed recess from behind, so that looking from the front the framing covered, say, a one-inch band (and any sewing or pinning) all round the edge of the dial, neatly framing the chapter-ring and spandrels. Spandrels of ornate winged cherub’s-head design, a style which was later used regularly on smaller domestic clocks, but not otherwise seen at this early date. Chapter-ring 15” diameter (inside 10”), with an outer ring for minutes, -60 twice, the minute hand turning once in two hours, with each division numbered; large fleur-de-lis half-hour marks, conventional hour numerals and inner quarter ring, the hour hand turning once in twelve hours; large subsidiary seconds ring marked -60 twice, calibrated in seconds (despite the fact that the clock originally beat two seconds), and numbered every ten seconds, the hand turning once in two minutes. Winding-hole shutter with engraved Tudor rose, the hole located at the centre of a decorative silvered plaque with pierced and engraved foliage, inscribed
MOTVS * ΛNNVVS
Sr Jonas · Moore · Caused · this · Movement
With · great · Care · to · be · thus · Made Ao1676 · by · Tho:Tompion.
Finely made hands of engraved and gilded brass, all believed to be original though the hour and minute hands have been repaired. The hour hand is probably missing a small engraved disc from its counter-side, and the minute hand is probably missing some decoration at the tip. With minimal pierced decoration and with counterpoising to minute and seconds hands, they are slender, graceful and give precise readings at close quarters.
The most robust of all Tompion’s clock movements (not counting the turret clocks), two heavy, shaped main plates 10½” x 8¼” are held by five thick pinned baluster pillars, and these plates accommodate the great- and 2nd wheels only. The 3rd, 4th and escape-wheels, together with the bolt for the maintaining power, all bear between the front-plate and a subsidiary plate pinned onto three smaller baluster pillars riveted to the inside of the back-plate. Each wheel is of a thickness commensurate with its task – of particular importance in long-duration movements to save energy. There is no friction work as such, the hands having long pipes which are friction tight – the hour-hand on the hour-wheel pipe, the minute hand on the extended 3rd wheel arbor. The inner side of one of the main pillars has been shaved – and this is believed to be an original feature - to give clearance to the gut-line which would have been taken up and round a pulley so that the weight descended to the left side of the clock. There is an element of doubt about this because the corresponding pillar in the second movement is not shaved. The lower two main pillars have threaded holes for securing the movement in its location, and its pair of turn-screws are certainly of early date and could have been used in the observatory.
The clock was converted for domestic use after its removal from the observatory and the original escapement, probably invented by Richard Towneley but made and modified by Tompion, was removed. The 30-pin dead-beat wheel and the pallets working across the direction of rotation were replaced by a 60-tooth recoil wheel for use with conventional anchor-shaped pallets. At the observatory the 2-seconds pendulum was suspended by either “a wedge-like spring”, or “on the pivots” – it is not clear which movement is which, vibrating from front to back. The wedge-like spring was possibly a spring of uniform thickness, but of tapering width, whilst the pivots were possibly a knife-edge arrangement. When converted to a conventional escapement for domestic use the movement was fitted with a standard back-cock with suspension for a seconds-pendulum vibrating from side-to-side. The escapement has recently been restored to a Townley-Tompion type with 30-pin escape-wheel, the pallets working across the direction of rotation of the wheel, and 2-seconds pendulum vibrating front-to-back. With fine ivory-handled steel winding-key. The duration would actually be about 56 weeks if all of the line on the barrel was used.
Wheel counts and (root) diameters.
No.1 (BM). No.2 (NMM)
Great wheel 112 (163mm) barrel with 28 turns. 112 (164mm)
2nd wheel 96 (95.5mm) pinion 8* 96 (95.5mm) pinion 8
3rd wheel 80 (68.0mm) pinion 8 (centre) 80 (69.0mm) pinion 8
4th wheel 48 (36.0mm) pinion 8 48 (36.0mm) pinion 8
Escape wheel 30 pinion 8**
*Extended square carries wheel of 60 gearing with hour wheel of 30.
** Neither movement has the original escape-wheel though both probably retain the original arbor and pinion. No.1 has recently (2001) been converted back to 30-pin wheel with pallets working across the direction of rotation, vibrating front-to-back. The original arbor and pinion were not used in the re-conversion, but have been placed in storage. It is currently running on a weight of 16 lbs on a single line. During testing it was possible to run the movement with a weight of 10 lbs, but this was insufficient to carry the hands.
Numbers and marks:
The pair of timepieces were made and installed at Greenwich in 1676 at Sir Jonas Moore’s expense and used by John Flamstead, ‘astronomical observator’ to Charles II (in effect, the first Astronomer Royal) for the next thirty-five years. Following his death in 1719 Flamsteed’s widow claimed possession of his instruments, including the clocks. Howse and Hutchinson suggest that some or all of Flamsteed’s instruments, including the clocks, might have gone to Christ’s Hospital where one of his former observatory assistants, James Hodgson, was Mathematical Master. Hodgson had married Flamsteed’s niece. In 1736 he presented one of the clocks – believed to be the NMM clock - to the Royal Society, but it is not known where this, the BM clock, spent the period 1719-1826. On 6th June 1826 a short notice which is believed to have referred to the BM clock was placed in the St James’ Chronicle:-
‘A discovery has lately been made of the chef d’œuvre of the celebrated Tompion, which has been so long lost. It was made for “The Society for Philosophical Transactions,” and is a year-going clock. It is a singular circumstance that a record exists, which states that Tompion was at work at work on this clock when the great plague broke out in London; and on the day he finished it, he himself was attacked with the pestilence. His friends removed him to the continent, where he died. On the dial there is this inscription:- “Sir James Moore caused this movement to be made with great care, anno Domini 1676, by Thomas Tompion”. Tompion was paid 100 guineas, and the clock was removed to the Society’s house, and there, in the confusion of the moment, it was placed in the lumber-room where it lay, without a case, exactly a century and a half. One thing wonderful attends this discovery – all the steel pins, on being cleared from dust, were found to be as brilliant as ever.’
Without a case – so this is less likely to be the Royal Society [NMM] clock, for which Peckover provided a case in the 1730s, and more likely to be this clock – which was in an ‘Empire mahogany’ case when it was sold in 1928. That case might have been provided by an astute auctioneer – a Mr Williams – who advertised in the Times, 16th January 1827, that he was to offer, at the London Auction Mart on the following day, ‘a valuable 12-month pedestal clock and regulator, with astronomical movement, by the celebrated Tompion’. Five days later The Weekly Register reported that ‘a 12-month astronomical clock, by Tompion, one of the celebrated three’, had fetched 58 guineas in the sale.
It is not known where this [BM] clock had come from and nor is it known who acquired it. We lose sight of it again, therefore, until it is next offered for sale nearly a hundred years later, and it is far from clear who sold it. It was booked in to Christie’s 23:5:1923 by Wallis & Son of 120, Pall Mall, SW1, and sold 19:6:1923, lot 146. It was knocked down to Percy Webster for 270 guineas and the under-bidder was David Wetherfield, who commented in a letter to J Drummond Robertson that he was ‘glad the clock has found a resting place at Mr Watts’. However, Webster sold it to Mr Roland Taylor of Philadelphia, and it is not known who Mr Watts was. When Mr Taylor was informed of its ‘horological interest and historical value for England’ he offered it to The British Museum at a price of £300, and it was duly acquired for the nation (Reg.no. M&ME 1928, 6-7. 1.). This is where the confusion over the identity of the seller in 1923 arises, because the museum trustees were informed that the clock ‘was lost sight of for a century, and on its reappearance was sold at Christie’s as the property of the Heralds College’. This is the first mention of that institution but the matter is further confused because H.Alan Lloyd, writing twenty-two years after the Christie’s sale, suggested that it had been sold by the Lowther family, ‘who might have acquired it through Sir James Lowther (d.1755), a Fellow of the Royal Society’. In a later paper Lloyd noted that ‘it is said to have been [in the Lowther family] for over 150 years, i.e. from 1775 or earlier’. The evidence for Lloyd’s statement is not known, and perhaps the most likely answer is that the Heralds’ College instructed Wallis & Son to dispose of it on their behalf. The clock has been on permanent display to the public at the British Museum since 1928, although it was removed to safety during the war.
There is a manuscript copy of the St James’ Chronicle note on a sheet pasted into a volume entitled Horological Miscellanea [Guildhall Ms.3982]. On the inside of the fly-leaf of this volume is written Begg 16 Crown Street Soho had April 1821 a Timepiece of Tompion with weights in good order for which they asked 31/6 [£1:11s:6d]. This is unlikely to be a reference to one of the Greenwich clocks.
Herbert Cescinsky, Flamsteed’s Clocks from Greenwich Observatory, Burlington Magazine, 1927.
Thomas Tompion his life and work, R.W.Symonds, 1951, fig.5.
H.Alan Lloyd, The Clocks of John Flamsteed, Horological Journal, 12:1948.
R. d’E. Atkinson and R.W.Symonds, The Greenwich Tompion Clocks, Country Life, 23:9:1949.
H.Alan Lloyd, The Original Clocks in Greenwich Observatory, Antique Collector, 8:1960, 10:1960.
Derek Howse, The Tompion Clocks at Greenwich and the Dead-beat Escapement, with an Appendix by Beresford Hutchinson, Antiquarian Horology, 12:1970 and 3:1971.
Francis Place and the Early History of The Greenwich Observatory, Derek Howse, New York, 1975.
Derek Howse, The Royal Observatory at Greenwich and Herstmonceux 1675-1975, vol.3, The Buildings and Instruments, 1975.
Beresford Hutchinson, Guardians of Greenwich Time, Vistas in Astronomy, Vol.28, 1985.
Alan Smith, A Reconstruction of the Tompion/Towneley/Flamsteed ‘Great Clocks’ at Greenwich, Antiquarian Horology, 12:1999.
- On display (G39/dc11)
- Acquisition date
- Britain, Europe and Prehistory
- Registration number