Source catalogue · individual objects
Object Catalogue
Individual objects described by auction houses, specialist dealers and collection catalogues. Attribution, dates and specifications remain source-reported unless independently established; rights clearance is pending.
Browse makers and their key pieces · Thomas Mercer profile
8 of 5699 objects · Page 1 of 1
Component · Balance, escapement & train part
Compensation balance with Kullberg's auxiliary
This chronometer compensation balance with Kullberg's auxiliary compensation is preserved in the Science Museum Group collection under object number 1929-71, credited to maker Thomas Mercer. The museum records the component's materials as bi-metallic arms intended for use with a steel balance-spring, measuring 5 mm by 40 mm by 37 mm and weighing 0.0091 kg. The assembly displays a central crossbar with a perforated center boss, curved bimetallic rim sections, large cylindrical brass weights, and slotted cylindrical timing nuts positioned on threaded terminal extensions.
Full description
collection.sciencemuseumgroup.org.uk · 1929-71
Marine chronometer · Two-day marine chronometer
Thomas Mercer Two-Day Marine Chronometer
This 20th-century marine chronometer by Thomas Mercer is mounted in a brass gimbal within a mahogany box. The circular silvered dial features black Arabic numerals, an upper subsidiary dial tracking state-of-wind up to 56 hours, and a lower subsidiary seconds dial marked with the number 28400. The dial is signed in script 'Thomas Mercer' at the center and marked 'THOMAS MERCER LTD ST ALBANS ENGLAND' along the outer lower periphery. The auction house reports that it houses a two-day chain-driven fusee movement with a compensated detent escapement and Harrison maintaining power, accompanied by a tipsy winding key stored in a corner bracket.
Full description
www.liveauctioneers.com · 0738
Marine chronometer · Two-day marine chronometer
Two-day Marine Chronometer by Thomas Mercer, no. 12827
The Science Museum Group collection holds this two-day marine chronometer made by Thomas Mercer in St Albans. Preserved under object number 1931-716, the instrument is housed within an ebony timber case fitted with corner stringing, flush brass carrying handles, and an inset mother-of-pearl plaque on the lid. The chronometer bowl rests in a brass gimbal mount alongside a locking mechanism. The dial shows Roman hour numerals, blued hands, an up-and-down state-of-wind indicator below XII, and an expanded subsidiary seconds dial above VI. Museum records list construction materials including brass, mother-of-pearl, glass, elinvar, and ebony.
Full description
collection.sciencemuseumgroup.org.uk · 1931-716
Marine chronometer · Two-day marine chronometer
Thomas Mercer Two-Day Survey Chronometer Model S.C. 2
This two-day survey chronometer, Model S.C. 2, was produced around 1955 by Thomas Mercer in St. Albans, England. Developed for surveying tasks requiring sidereal time, it features a four-pillar, single-chain fusee movement with Harrison's maintaining power, an Earnshaw-style spring detent escapement, a helical palladium balance spring, and a split bimetallic balance. Its four-inch silvered dial presents a 24-hour display, subsidiary seconds with an aperture revealing an electrical contact wheel, and an up/down reserve indicator. The movement is mounted in an aluminium casing fitted with external electrical contact terminals and a start/stop control.
Full description
auctions.dreweatts.com · 629
Marine chronometer · Eight-day marine chronometer
Thomas Mercer Eight-Day Ship's Chronometer
This English eight-day marine chronometer is attributed by the source to Thomas Mercer of St. Albans and dated to the first half of the 20th century. The instrument is mounted in a gimbal ring inside a brass-bound wooden box equipped with brass side-carrying handles. Both the case and dial are numbered 1184N. The dial features Roman numeral hour markers, blued hands, an up-and-down state-of-wind indicator below XII, and a subsidiary seconds register above VI. Accessories include a winding key and a lock key. The source reports that the movement takes a wind but does not run.
Full description
freemansauction.com · 315
Marine chronometer · Two-day marine chronometer
Thomas Mercer late 19th century 2.5 day marine chronometer
This late 19th-century marine chronometer is attributed to Thomas Mercer of London. Suspended in a gimballed brass bowl within a brass-bound teak box, the chronometer features a 2.5-day duration movement reported to incorporate a Poole auxiliary balance. The silvered dial carries black Roman hour numerals, outer minute indices, a subsidiary seconds dial, and a state-of-wind indicator below twelve o'clock. Engraved medal motifs commemorate exhibition awards from Paris 1867 and Philadelphia 1876. The dial is signed and numbered 5548, while the case is source-reported to bear a label for retailer H. Hughes & Son Ltd marked with number 1570.
Full description
auction.gorringes.co.uk · 249
Clock · Desk clock
Thomas Mercer Brittanica Table Chronometer
The Thomas Mercer Brittanica is an octagonal table chronometer created as a unique piece in collaboration with British furniture designer Jake Phipps for the Only Watch 2015 auction. The case, base, and dial bezel are fashioned from AISI 316 stainless steel combined with white leather and extra-white crystals. Powered by the hand-wound calibre TM0802 with a spring drive and steel chain fusee system, it provides an 8-day power reserve and incorporates a spring detent escapement with an ovalising balance oscillator visible through an upper aperture. The blue central dial displays a celestial map representing Geneva's night sky on 7 November 2015 at 5 PM, complemented by a small seconds register at 12 and a power reserve indicator at 6.
Full description
www.phillips.com · 28
Marine chronometer · Two-day marine chronometer
Thomas Mercer Two-Day Marine Chronometer No. 19116
This Thomas Mercer two-day marine chronometer is housed in a two-tier mahogany deck box. The instrument features a four-pillar single chain fusee movement with Harrison’s maintaining power and an Earnshaw-type spring detent escapement. It includes a split bimetallic balance with cylindrical compensating weights and a helical palladium balance spring. The 4-inch circular silvered dial displays Roman numerals, a central subsidiary seconds dial, and a power reserve indicator marked UP/DOWN. Uniquely, the dial contains a side aperture exposing electrical contacts and terminals on the case side, configured to emit a one-second pulse. The chronometer is mounted in gimbals within a lacquered brass bowl with a shuttered winding aperture at the rear. The mahogany box features a glazed viewing panel in the lid and an applied brass plate identifying the maker, location, and serial number.
Full description
www.invaluable.com · 183