Gary Heschenroeder, age 14, of Desoto, mo., for his question.

How does the X-Ray work?

William Konrad roentgen was experimenting with cathode rays in wurzburg, germany, in 1895, and while working in a dark room and studying fluorescence, he came up with some information that led to the discovery of what he called the x ray. In his honor, X rays are today also called roentgen rays.
X rays are a form of electromagnetic radiation, similar to light but having shorter wavelengths. The rays are capable of penetrating solids.
Unlike cathode rays, from which X rays are produced, they are not deflected by electric charge. They are commonly produced in glass tubes which contain two electrodes  the anode and the cathode.
When a high voltage is applied between electrodes, streams of cathode rays, or electrons, leave the cathode, are accelerated across the tube and, after attaining a high velocity, they strike the anode which is made of platinum, tungsten or some other metal of high melting point. X rays are then given off in the process of the sudden stopping of the electrons.
X rays penetrate many substances to a greater or lesser degree, depending on the material. wood and flesh are easily penetrated, but metal is more difficult. Penetrating power depends upon the energy of the X ray. the more penetrating hd " rays. They are produced in tubes operated at higher voltages than tubes that produce "soft" or less penetrating rays.
The penetrating property of X rays is used in making X ray pictures, which are also called radiographs or skiagraphs. The darkness of the shadows produced upon the photographic plate depends upon the degree to which the different substances can be penetrated by the rays. A shadow like picture of an arm bone, recorded on an X ray, can show if there is a break or a crack.
X rays can destroy living tissue and can also cause burrs to human flesh if it is exposed to their action for too
long a period. For this reason, care is taken when giving X rays, and technicians retire from the room or wear special shields.
The destructive power is used to great advantage in X ray therapy, with treatments providing benefits not found in other medical form.
X rays are also used for the examination of many merchandise items. Jewelry, for example, can be checked for defects and also tested to see if it is genuine and not an imitation. Old master paintings have also been X rayed as a way of establishing their authenticity.