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In favourable conditions of low temperature and low oxygen concentration, archaeological waterlogged wooden artefacts, such as shipwrecks, can survive with a good state of preservation. Nevertheless, anaerobic bacteria can considerably degrade waterlogged wooden objects with a significant loss in polysaccharidic components. Due to these decay processes, wood porosity and water content increase under ageing. In such conditions, the conservation treatments of archaeological wooden artefacts often involve the replacement of water with substances which fill the cavities and help to prevent collapse and stress during drying. The treatments are very often expensive and technically difficult, and their effectiveness very much depends on the chemical and physical characteristics of the substances used for impregnation. Also important are the degree of cavity-filling, penetration depth and distribution in the structure of the wood. In this study, the distribution in wood cavities of some mixtures based on polyethylene glycols and colophony, used for the conservation of waterlogged archaeological wood, was investigated using synchrotron radiation X-ray computed microtomography (SR-µCT). This non-destructive imaging technique was useful for the study of the degraded waterlogged wood and enabled us to visualise the morphology of the wood and the distribution of the materials used in the wood treatments. The study has shown how deposition is strictly related to the dimension of the wooden cavities. The work is currently proceeding with the comparison of synchrotron observations with the data of the solutions viscosity and with those of the properties imparted to the wood by the treatments. [ABSTRACT FROM AUTHOR]

SEM-EDX quantitative analyses were performed on 91 samples of vessel glass originating from a number of sites throughout Tuscany. A comparison with Venetian glass data is made in order to evaluate differences in glassmaking materials. The compositions of the samples provide clues about the different raw materials used in relation to recipes that changed slightly during the period covering the late Middle Ages to early Renaissance. Two kinds of ash used as a fluxing agent were identified, one of which is of east Mediterranean origin while the other is likely to be Spanish. Two types of silica sources were also found. One of these was recognized as being quartziferous river pebbles, while the other is proposed to be local sand. [ABSTRACT FROM AUTHOR]