The two facts which the roentgenologist must know about a beam of x-rays which he is going to use are its penetrating power and its intensity. The penetrating power of a beam of x-rays produced by any set of technique factors can be determined from charts prepared from the experience of many investigators, including the authors, who have produced a set of 160 charts for that purpose. The charts are drawn actual size and show the distribution of x-rays in water with all the variations in technique commonly used in therapy, - water being used as a medium because the absorption and scattering of x-rays in water is practically the same as in tissue. The use of the charts is simple and direct.
Proceedings of the Iowa Academy of Science
©1924 Iowa Academy of Science, Inc.
Erskine, Arthur W. and Smith, Scott W. Jr.
"The Relative Values of the Selenium Cell and the Ionization Methods of Measuring X-Rays in Roentgenotherapy,"
Proceedings of the Iowa Academy of Science, 31(1), 399-402.
Available at: https://scholarworks.uni.edu/pias/vol31/iss1/136