Jacobus Markwick

Jacobus Markwick, London, circa 1680. Very rare and fine silver pair cased watch with early "Barrow" straight line balance spring regulator. Outer double body, polished, with concave bezel and square hinge. Inner double body, bassine with split bezel and loose-ring pendant, polished, the back with winding hole shutter. Silver champleve with Roman numerals, half and quarter marks, centred with an engraved rosette. Single blued steel hand. Hinged gilt brass full plate with pierced tulip pillars, fusee with chin, short train, plain steel threearm balance, Barrow worm screw regulator, openwork gilt brass English cock with irregular foot, allowing one to see the newly invented balance spring. Signed on the back plate. Diam. 52 mm. Notes The straight line balance spring regulator It is generally the case that in the extensive literature recording the history of English Horology, the invention of the "straight line" or "endless-screw" regulator has been attributed to Nathaniel Barrow (Apprentice 1653, Clockmaker's Company 1660, Master 1669). In France, the same invention has been attributed to Jacques Gloria, whose working dates are comparable. Although the latter was virtually alone in France to employ the idea, there were perhaps a handful of English makers who used it, albeit rarely. It may be that Barrow's claim is based more on subsequent writings than on historical fact. A slightly earlier system employed by Henry Jones, used a completely straight spring mounted Read more…