Grey's biography of the man who discovered x-rays begins with a dramatic reconstruction of the classroom misunderstanding that led to his expulsion and disqualified him for the certificate he needed for admission to University. (Via a devious route through inferior schools, Roentgen did attent University unofficially and later even earned a Ph.D. in the new field of experimental physics, without ever having completed a course in the subject, by writing a ""sufficiently good"" thesis.) Except for that opening incident Grey avoids the popular, fictionalized style that characterizes Esterer's Discoverer of X Ray (1968). Esterer though is at least as thorough on the background, occasion and public reaction to the discovery, and it would be difficult to arbitrate between the two versions' occasional differences in detail or interpretation. Grey's account does have an air of authenticity and if there is room for yet another YA biography of Roentgen (CBIP lists three predecessors) this one is sufficiently functional.