A multidisciplinary investigation on a pair of Leonardesque canal lock gates

Leonardo's Codex Atlanticus depicted a detailed drawing for an improved wooden canal lock to control the water flow in Milan's canal system. Museo Nazionale della Scienza e della Tecnologia “Leonardo da Vinci” in Milan has been conserving two pairs of canal gates in its storage for more than fifty years, until a complete and multidisciplinary study was launched to deeply examine one of the pairs. Both historical and scientific research teams joined in their efforts. While historical research has recreated the provenience of the gates until their arrival at the Museum, the scientific analyses were a new opportunity to help the reconstruction and characterization of the canal gates' history, enlightening the construction technique, the structural modifications over time and the conservation conditions. The multidisciplinary investigations involved radiographic analyses, 14C dating and the chemical characterization of the wood present in the gates. Through the radiographic analyses, it was possible to show the structure of the gates, the joints and the position of the metal components. Eighteen micro-samples were collected on selected areas of the gates and provided interesting results: artifacts dating the results span over four centuries. Furthermore, the degradation of the wood was studied by estimating the amount of lignin and holocellulose, and the distribution of their molecular weights.