In 1930 I succeeded in obtaining the first laminagraphs. I was followed in rapid succession by Ziedses des Plantes (1931), Bartelink (1932), and by Grossmann and Chaoul (1935). Since then, the method has been generally adopted under the names of planigraphy, stratigraphy, laminagraphy, and tomography. Preparatory experimental work tending toward cross-sectional study of the body was made by Kieffer in 1938, and by Amisano in 1944 and 1946. Early in 1947 more fruitful experiments on cross-sectional laminagraphy were conducted by myself and by Frain and Lacroix. Later in 1947 I was able to obtain sat isfactory crosssectional studies of the living patient. Since then, with the help of my coworkers, I have been able to perfect this new method of examination. This method we have called axial transverse laminagraphy. The geometrical factors involved are shown in Figure 1. The roentgen beam is directed with considerable obliquity to the center of the desired cross section and reach es a film which is carried on ...