Ronnie Bernhardt, age 11, of Lyons, N. Y., for his question:
What are X rays?
Our world, and perhaps the whole universe, teems with various kinds of energy which exist in the form of waves. These energy waves could be compared to the ripples when you toss a pebble into a pond. However, most of these energy waves are invisible to our eyes because they are so small and they travel s o fast.
One form of wave energy brings us our radio and television signals. The receiving sets change it into things we can see and hear. Sunlight is another form of wave energy. Other extremely short waves of energy carry messages from the Pioneer V satellite which is now busy orbiting the sun. Our modern world is full of gadgets for translating these waves of energy into sights and sounds which we can see and hear.
The story of X ray is the story of still another form of wave energy. This form of energy was discovered in the year 1895 by Wilhelm Roentgen of Germany. Light energy, of course, does not pierce a solid object which is why we cannot see our bones. The energy discovered `by Roentgen does pass through solid objects at least to some degree. It passes through flesh, but not through bones.
In no time at all, this discovery was put to good use in the world of medicine. Roentgen's rays were used to take a peek inside the human body. What’s more, they were used to take pictures of the bones inside the living body. The rays are turned on, pass through the body and strike a photographic plate on the other side. Bones, which are denser than flesh absorb more of the rays, leaving dark areas can the photographic plate.
Roentgen named his discovery X rays because he did not know what they were Officially this amazing form of energy is called Roentgen rays in honor of the discoverer.
X rays penetrate further than ordinary light because they travel on shorter wave lengths. There short, pulsing waves can wriggle through and around atoms with great ease. We can step them up to even shorter wave lengths. Those of fairly short wave lengths are called soft X rays and soft X rays are used in medicine.
X rays with very short wave lengths are called hard X ryas. They have endless jobs to do in the world of industry for they can pierce far deeper than the soft rays. Hard X rays are used to spot flaws in metal castings and all kinds of jobs were it 3.s necessary to peek inside a solid object.
Hard X rays are also used to study crystal formations. Here a picture is taken of the waves which bounce off each crystal surface. The result is a design as dainty as a doily. Each substance has its own crystal formation and an X ray picture of this structure is as reliable as a fingerprint.