Water-logged leather found in the underwater excavation of the wreck Mary Rose (16th century English; portsmouth Harbour, U.K.) were stabilized by vacuum freeze-drying. Artifacts were immersed in 10% PEG 400 for up to two weeks, frozen in a deep-freeze, then freeze-dried at 20 degrees C (sic). (Abstractor's note: The temperature should probably read -20 degrees C. ) Any severe iron-staining was first removed using 5% oxalic acid for one hour, then washed three days before being immersed in the PEG 400. Treated leather is stored between 16-22 degrees C in 50-60% R.H. -- AATA