The vacuum impregnation of two organ wind chests situated in the church of St. Ignatius in Jihlava (Czechoslovakia) dating from the first half of the 18th century is described in detail. One was made of limewood, the other of oak, spruce, and maplewood. After wood-worm disinfestation by gamma radiation (Co⁶0</sup>), the organ wind chests were partly disassembled and cleaned, and the leather parts unglued. The wind chests were then wrapped in polyethylene mesh and then within of an 18% solution of Solakryl BMX in toluene polyethylene film. Vacuum impregnation of an 18% solution of Solakryl BMX in toluene was carried out within this polyethylene cover. (Solakryl BMX is a 36% solution in xylene of a copolymer of butylmethacrylate and methylmethacrylate.)