Presented in 1999, the Datograph was, at the time, a technical bewilderment for the watch world and collectors alike. This extraordinary piece is driven by an in-house manual wind chronograph movement, the calibre L951.1. Together with the Datograph Perpetual, Double Split and the 1815 Chronograph (see Lot. 2993), this movement features a jumping minutes hand where the minute counter hand jumps at the exact moment the chronograph hand hits 60. As trivial as it may seem, it is an immensely complex mechanism to implement and to the best of our knowledge, A.Lange & Sohne is the only watchmaker in the current market that offers such feature in their chronograph movements except the calibre 13.33 by Longines dating back to the 1930s.