GEORGE L. CLARK (1892 - 1969). Applied X-rays. New York: McGraw-Hill, 1927.
Clark received his A.B. degree at DePauw University in 1914 and in the same year was awarded a M.S. degree in chemistry from the University of Chicago. He served as an instructor in chemistry at DePauw, and then returned to the University of Chicago to work toward his Ph.D. degree, which he received in 1918. He then held several academic positions, most notably as an assistant professor of Applied Chemical Research at Vanderbilt University, at Harvard (where he was a National Research Council fellow), and the Massachusetts Institute of Technology. In 1927 he joined the faculty of the University of Illinois at Urbana-Champaign. He was the founder and first chairman of the Electron Microscope Society, chairman of two divisions of the American Chemical Society, and Editor-in-Chief of several scientific encyclopedias, including The Encyclopedia of Chemistry, The Encyclopedia of Microscopy, and The Encyclopedia of Spectroscopy.
Clark was an expert in the application of X-rays in both the research lab and in the real world, and frequently introduced new instrumental methods based on X-rays to solve important problems. For example, he used X-rays in stress analysis, determining whether particular metals (such as those used in propellers) were defective. In addition, he successfully used X-rays to determine the molecular weights of the macromolecules found in the rubber plant, an issue that had intrigued scientists for years.
In 1945, Clark developed a powerful X-ray generator that could withstand the heat generated by up to 50,000 volts of electricity. Clark's new device meant that X-ray pictures could be taken in seconds rather than minutes, thus greatly improving the utility of X-rays in many different applications.
"George Lindenberg Clark and High-Intensity X-ray Tubes," American Chemical Society, National Historic Chemical Landmarks website (http://www.acs.org/content/acs/en/education/whatischemistry/landmarks/noyeslaboratory.html#george-lindenberg-clark-biography, accessed 30 Jan 2012).