• frosted gilt and partially skeletonised movement, spring detent escapement, free-sprung, bi-metallic compensation balance with blued steel helical spring, diamond endstone, steel detent with separate cock and dovetail adjustment, fusee and chain • glazed cuvette with winding hole • white enamel dial, Roman numerals, gold spade hands, large subsidiary seconds with blued steel hand, outer minute track • 18k yellow gold engine-turned case with blank central cartouche, gold pendant, case with London hallmarks for 1869, case with maker's mark AS for Alfred Stram • movement signed Barraud & Lunds, 41 Cornhill, London, No. 3/127, dial signed and numbered, the ebauche with maker's mark J.P. for Joseph Preston & Sons

Terence Camerer Cuss, The English Watch 1585-1970, pp. 406-407, pl. 259

For a nearly identical pocket chronometer and extensive discussion of this construction by Barrauds & Lund, see Jagger," Paul Philip Barraud, The supplement", Antiquarian Horological Society 1979, pp. 215, 223, pl. XXVII a-b. Jagger notes that the watch in figs. a,b is a "half chronometer" and credits Lund for its invention citing Lunds Obituary. 

Barraud & Lunds are listed in Brian Loomes, Vol.2 Watchmakers♌ and Clockm🥃akers of the World, working in 1839-1863.