Ed Vebell, a skilled illustrator, said he developed the ability "to analyze a subject and grasp its essentials at a glance and draw it later from memory." Vebell worked as a courtroom illustrator for Stars & Stripes at the Nuremberg war trials. Looking through field glasses from the spectator's gallery, Vebell could draw the defendants directly in fountain pen and used only "a moistened thumb for the middle tones."
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Verbell Courtroom Art from the Nuremberg Trial