Collection online

weight-driven clock / regulator / long-case clock / clock-case

  • Object type

  • Museum number


  • Escapement

  • Description

    Long-case regulator in walnut case with glazed trunk door; hood with break-arch pediment decorated with egg and dart moulding, fluted corner pillars with Corinthian capitals and central gilded ball finial on a plinth; gilded-brass dial with matted centre and cherub spandrels; applied silvered-brass chapter-ring with Roman hour numerals, minutes numbered every fifth division in Arabic and with integral subsidiary seconds dial; blued-steel hands; massive weight-driven eight-day movement with Harrison's maintaining power and Continental stop-work; four-legged gravity escapement with zinc-iron rod and lead bob compensation pendulum.


  • Producer name

  • Date

    • 1875-1885
  • Production place

  • Materials

  • Technique

  • Dimensions

    • Height: 226 centimetres
    • Width: 48.5 centimetres
    • Depth: 30.5 centimetres
    • Weight: 223 kilograms (Whole clock)
    • Weight: 10 kilograms (Driving weight)
  • Inscriptions

      • Inscription Type

      • Inscription Content

  • Curator's comments

    Text from 'Clocks', by David Thompson, London, 2004, p. 158.
    James Brock
    Longcase regulator
    London, c. 1880
    Height 225 cm, width 48.5 cm, depth 30.5 cm
    In March 1859, having been tested and refined in the workshops of E. J. Dent, the Great Clock (Big Ben to the uninitiated) at the Palace of Westminster was finally installed and working. The mechanism of this world-famous clock had been designed by Edmund Beckett Denison (Lord Grimthorpe) to specifications laid down by George Biddle Airy (1801-1892), the Astronomer Royal. Work had begun on the clock in 1852 after an eight-year dispute with Benjamin Lewis Vulliamy, who lost the contract for building the clock largely because he would not submit plans and estimates until two years after the tender for the clock was put out by the government.
    It was the foreman in Dent's workshops, a man called James Brock, who oversaw the construction ofthat enormous machine. Brock later left Dent's employ and set up in business on his own account in George Street, Portman Square, London, and it was here that this regulator was made.
    In many ways this clock is old-fashioned in its appearance, with a traditional hooded case in a longcase style which to a large extent had died out as a fashion in London. However, the light-coloured wood for the case and the bold egg-and-dart moulding at the top show it to date from about 1880 when it would have made an excellent addition to any fine jeweller's shop.
    The movement shows Brock's connection with the Westminster clock in having a four-legged gravity escapement of Grimthorpe's design and a zinc-iron compensated pendulum. The massive plates show that typical disregard for economy of materials in the Victorian era. The weight line passes up above the movement over a barrel/pulley in order to keep the weight to the side clear of the pendulum and escapement arms.
    James Brock died in 1893 at the age of sixty-seven. Lord Grimthorpe later referred to him in a letter he wrote to the 'Horological Journal' in 1902, concerning his gravity escapement:
    "I am sitting now in front of the very first of them, which was made straight off from my drawing in 1852, and it has been going ever since, either in London, while I kept a house there, or here. I am sorry to say that its actual maker, James Brock is dead. He was an excellent and charming man, who first worked for me at the original Dent's, in the Strand, and who built a sufficient factory in a stable-yard in that region, where we made the Westminster clock and sundry other large ones."
    Purchased in 1988.


  • Bibliography

    • Thompson 2004 p.158 bibliographic details
  • Location

    On display: G39/od

  • Acquisition name

  • Acquisition date


  • Department

    Britain, Europe and Prehistory

  • Registration number



If you’ve noticed a mistake or have any further information about this object, please email: 

View open data for this object with SPARQL endpoint

Object reference number: MCC3185

British Museum collection data is also available in the W3C open data standard, RDF, allowing it to join and relate to a growing body of linked data published by organisations around the world.

View this object

Support the Museum:
donate online

The Museum makes its collection database available to be used by scholars around the world. Donations will help support curatorial, documentation and digitisation projects.

About the database

The British Museum collection database is a work in progress. New records, updates and images are added every week.

More about the database 


Work on this database is supported by a range of sponsors, donors and volunteers.

More about supporters and how you
can help