John Shelton the Younger London clockmaker John Shelton is highly regarded for his technical prowess in clockmaking. He made one of the earliest equation mechanisms and is principally known for making five astronomical regulators for the Royal Society to measure the transits of Venus. These data would be used to determine, by trigonometry, the distance between the earth and the sun. Born in 1702, Shelton is believed to have been the son of a London clockmaker of the same name, John Shelton. Shelton the Elder worked on Shoe Lane, off Fleet Street, in London. Undoubtedly immersed in the business of clockmaking from a very young age, Shelton the Younger was initially apprenticed to clockmaker Henry Stanbury in 1712 and became a Free Brother of the Clockmakers’ Company in 1720. During the early part of his career, he produced the Teiger Shelton Solar Longcase, dated 1736.[1] A technical achievement, this clock is possibly one of the earliest surviving examples of an equation mechanism in its final and most complicated form. Shelton was also the first English maker to apply a concentric solar hand to an equation clock – see the concentric minute hands on the Teiger Shelton. Around the time that the Teiger Shelton Solar Longcase was made, King George III presented an astronomical clock by Shelton to Gottingen observatory, and many of Shelton’s later regulators were sent to observatories such as Radcliffe, Kew and St Petersburg. There are also two other equation clocks by Shelton in the Spanish Royal Collection.[2] Both are similar in design to the Teiger Shelton. By 1752, Shelton was working closely with master clockmaker George Graham. We know this from a letter to the Royal Society written by James Short, a Scottish telescope maker who was a Fellow of the Society from 1737. In his message, Short describes Shelton as ‘the principal person employed by Graham in making astronomical clocks’. The professional arrangement between the two clockmakers endured throughout the rest of Shelton’s career, and evidence of this collaboration can be seen in the regulators discussed below that feature Shelton–Graham movements. During the 1760s, Shelton made five regulators for the Royal Society. These were commissioned expressly for use in collecting data on the transit of Venus in 1761 and 1769. Of the five, we know the whereabouts of four. One of these could be the Shelton longcase regulator, dated to 1756, exhibited in the World Cultures Gallery in the National Museum of Scotland (Museum Reference T.1978.1). Not all its history is known, and it is unclear whether it is one of the five Shelton regulators purchased by the Royal Society. We do know that it was well travelled. In 1754, Astronomer Royal Nevil Maskelyne used it for taking gravitational measurements at Schiehallion in Perthshire, Scotland. It also served as the master clock at the Kew Observatory in London, the Ben Nevis Observatory in Scotland, and the Eskdalemuir Magnetic Observatory also in Scotland. It bears the marks of the observatories at Kew and Ben Nevis: KO and BNO / 33. There is also a longcase Shelton regulator in a veneered mahogany case with three legs, made around 1760 and held in the Collection of the Royal Society.[3] Then there is the John Shelton regulator made around 1764 and forming part of the Special Collection at St John’s College, Cambridge. It is described in full by Howse and Hutchinson.[4] Although it clearly had a long working life, little of this regulator’s history is known. It has a Shelton–Graham movement and was initially signed by both men. This original signature was removed at a later point in its working life, and a new observatory or shop name was added in a curve below the centre. When the regulator was rediscovered later in the 20th century, the new owner recognised it as a Graham–Shelton regulator and had the original signature restored. Next is the clock movement for a Shelton regulator, dated around 1768, at the Science Museum in London (Object Number: 1914-591 Pt1). This movement also had a long working life. According to the Science Museum, this clock was despatched on a variety of voyages during the 1800s, including aboard William Edward Parry’s search for the Northwest Passage in 1819–20. Later, the movement was fitted into a wooden case made in the 1880s, and then the clock was in use by the United States Coast and Geodetic Survey. Finally, there is the Shelton regulator, made around 1769 and kept at the National Maritime Museum (Object ID: ZBA1765). The movement in this regulator is described as a ‘typical Graham/Shelton form’. Although there is no way to confirm exactly which of the above Shelton regulators were used by Captain James Cook, we know that he took one to Tahiti for use in the 1769 transit of Venus observations, and that two of the others accompanied him on later voyages. In 1766, Shelton became one of first Liverymen for the Worshipful Company of Clockmakers. Despite his success, Shelton apparently ran into money problems towards the end of his career. In 1777, he asked the Royal Society for financial relief. The Society passed his request to the Board of Longitude, who then forwarded it to the First Lord of the Admiralty in hope of a petition to King George III on Shelton's behalf. End Notes [1] Carter 2021, 206–209, Catalogue No. 42. [2] Colón de Carvajal 1987, 41. [3] Royal Society Archive Reference Number MOB/029. [4] Howse and Hutchinson 1969, 289–291. References Carter, J. 2022. The John C Taylor Collection: Part II (Selling Exhibition Catalogue, Carter Marsh & Co). Winchester: Carter Marsh & Co. Colón de Carvajal, J. R. 1987. Catálogo de relojes del Patrimonio Nacional. Madrid: Patrimonio Nacional. Howse, D. and B. Hutchinson. 1969. ‘The saga of the Shelton clocks’ in Antiquarian Horology: 281–298. Source For the John Shelton regulator, made around 1769, at St John’s College, Cambridge, see https://www.joh.cam.ac.uk/library/special_collections/artefacts/shelton_regulator.
