(I) X-rays are a form of electromagnetic radiation that
readily penetrates human flesh. (II) As soon as the
existence of X-rays had been reported, the medical
applications with radioactive materials were recognized.
(III) However, it took quite a while longer for people to
detect the dangers of these mysterious new rays. (IV) All
X-rays are not man-made; extremely hot stars, such as
neutron stars, also produce huge amounts of X-rays.
(V) For example, Major John Hall-Edwards, who helped
pioneer the use of X-rays in medical treatments, lost an
arm because of excessive exposure.