In the case of the edge and core Mary Rose samples, the PEG treatment appears to have preserved the oxidative degradation state of the wood as it was before the ship was raised from the seafloor, as there are clear differences to the untreated sample and between the treated core and edge sample. The edge sample has an S/G ratio higher than the core sample, but lower than that of modern oak, consistent with the century-old wood of SB Tollesbury, indicating that some loss of syringyl compounds has occurred. The low S/G ratio of the core of the Mary Rose sample is in alignment with 437 years of burial . It is well documented by a number of techniques including pyrolysis-GC-MS, that syringyl components degrade more quickly than their corresponding guiaiacyl counterparts during burial. Intriguingly, the Ac/Al ratios for the core and edge samples are respectively lower and higher than those of modern oak, suggesting that different processes dominated in different locations within the wooden beam of the hull.