Part I presents an update on the timbers from the Batavia. Since 1976 a large section of ship's timbers from the wreck of the Batavia (1629) has been undergoing treatment in polyethylene glycol 1500 at the Conservation Laboratories of the Western Australian Museum. In order to follow the progress of the treatment it is useful to know the extent of the polyethylene glycol penetration. The use of infrared spectroscopy in the quantitative analysis of polyethylene glycol was first suggested in 1981. Part II covers the treatment of waterlogged leather from three different marine environments and the retreatment of lanolin impregnated leather. Aqueous solutions of polyethylene glycol 1500, Luviskol K-30 (which is a polypyrrolidone also known as Nylon-4), and glycerol were used, followed by freeze-drying in most cases. Shrinkage and weight loss data are tabulated and a method of treatment is proposed for all types of waterlogged leather. Some comments are also made on the successful treatment of waterlogged rope and matting.