Radiography, the use of penetrating radiation to produce shadow images of the internal structure of materials, has been with us since Roentgen made his discovery of x rays in 1895. However, applications of radiography in the earth sciences and in the related field of soils engineering have, until recent ly, been slow to develop. Bruhl reported optimistically on applications in paleontology as early as 1896 and there have been additional reports through the years. However, very few paleontologists adopted the method and the significant literature is relatively restricted. In soil mechanics,...