Density and shrinkage were measured in samples of old wood preserved in a glacier, burial grounds, house settlements, harbour installations and ships sunk in the sea. Time of exposure ranged from about 300 to 100,000 years. Density was found reduced in most cases and shrinkage increased. In oak, density was reduced up to 0.13 gr/cm3 (at 12% m.c.) and a tangential shrinkage value of 62.16% was measured. Irrespective of time of exposure and loss of material, old wood retains its gross structural characteristics as long as it remains waterlogged.