An unusual George II black japanned table clock with Dutertre`s duplex escapement Attributed to Robert Breckenrig, Edinburgh, circa 1725 The five pillar twin fusee bell striking movement with escapement composed of two escape wheels of varying diameter mounted on the same arbor which alternately engage with cranked pallets regulated by a standard verge type short bob pendulum, the backplate finely engraved with a grotesque mask within Ho-Ho bird inhabited foliate scrolls and a narrow ropetwist border, the 7 inch brass break-arch dial with calendar aperture to the matted centre within applied silvered Roman numeral chapter ring and Indian mask and scroll cast spandrels to angles, the arch now with silvered circular signature boss inscribed Robert, Breckenrigg, EDINBURGH within herringbone border within a herringbone border and flanked by conforming mounts, the inverted bell-top case with foliate cast brass carrying handle above front door with scallop shell and scroll cast brass frets to upper quadrants, the sides with ruby glazed windows above blanked break-arch apertures, the rear with conforming glazed upper quadrants over break-arch aperture, the exterior decorated in raised polychrome and gilt with chinoiserie designs within foliate borders throughout, the cavetto moulded base with later brass bun feet, (the original signature boss bearing re-engraved script Tho. Tompion, LONDINI over erased indistinct traces of original signature is present with the clock), 44cm (17.75ins) high excluding handle. Provenence: Almost certainly the clock described by Thomas Reid of Edinburg in his 18 work A TREATISE ON CLOCK AND WATCH MAKING on page 238. Previously sold in these rooms (unattributed) on Tuesday 22nd February, 2012, lot 251. The escapement in the current lot appears to be an early/contemporary application of the duplex arrangement as designed by the French horologist Jean Babtiste Dutertre (worked 1715-42), and was perhaps conceived as attempt to improve on the tic-tac escapement. The principle benefit is that the wear rate is greatly reduced as the pallets only engage once with each tooth for each rotation rather than twice (once from either side) for the standard tic-tac arrangement. In essence one wheel provides the entry action of a recoil arrangement and the second controls the exit. This division of the function of the escapement between two wheels allows the teeth on each wheel to be of a heavier profile than on the single escape wheel of a tic-tac escapement, further improving reliability and longevity. Dutertre`s design is illustrated in Reid, Thomas A TREATISE ON CLOCK AND WATCH MAKING plate IX/48 and is briefly described on page 238. More importantly on the following page Reid also comments: It is more than fifty years since we saw a small spring clock having this escapement, made by a very ingenious clock-maker of this place whose name was Robert Breckenrig. When this is considered alongside the overall style, design and layout of the present movement (which is typical of English/British work and can be confidently be dated from the second quarter of the eighteenth century) it would seem highly appropriate to suggest that it is the 'spring clock' to which Reid refers above. This is further supported by the fact that when previously offered in these rooms it had been consigned from a vendor who resided near Loch Ness, Scotland. In light of the above the vendor has gone to the trouble of having a signature boss made and engraved with Breckenrigg's name to replace the previous boss from which then original signature had been erased and replaced with that of Tompion however the earlier boss is also included in the current lot.Overall the current lot has survived in original condition (including the escapement which is unaltered and has always been with the clock) and would appear to have historical significance in the context of Scottish horology and escapement development.