J.AURICOSTE rare sidereal time 1/2-second- chronometer timer, Switzerland / France around 1890, varnished brass case by bezel screwed down, inserted in 3-piece mahogany-box, enamel dial with central second, minute counter at 12, blued original hands, brass 2/3-board- movement with pivoted detent escapement, 14 jewels, heavy compensation-balance with Breguet-hairspring, measures approx. 12 x 8 x 4,5 cm, needs to be overhauled, condition 2