fragment (IMAGE) Johannes Gutenberg Universitaet Mainz Caption Carbonate fragment from the Barbegal mills, formed on wood of the mill machinery, with imprints of wood and traces of woodworking Credit photo/©: Philippe Leveau Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.