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This story was published on September 20, 1996
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The following article is written for the occasion of the 100th anniversary of the discovery of X-Rays.

Wilhelm Konrad Roentgen: Discoverer of X-Rays

Ursula's History Web

Wilhelm Konrad Roentgen was born on March 27, 1845, in Lennop, a small town in the Rhineland of Germany. His father was a wealthy textile merchant, his mother was a Dutch lady born in Appledoorn, Holland. During his boyhood years Wilhelm already had a passion for experiments, but above all he loved nature. In school he was not very successful, not so much because of his performance but because of his behavior. He had trouble with his teachers, resisting their authority which finally led to his dismissal. Wilhelm ended his school years without any certificate. Because he wanted to pursue an academic career, he had to find another way to achieve his goal. A friend suggested the newly established Poly-Technical Institute in Zurich, Switzerland. There, he applied himself and easily earned a degree in mechanical engineering. He did not know what he wanted to do with this degree, so for awhile he did nothing. He caroused with his friends. It was during this time that he met Berthe Anna Ludwig, who later became his wife.

He decided to continue with post-graduate studies with the encouragement of Dr. August Kuntz. By studying hard and concentrating on the task at hand, he was able to obtain a doctorate in physics with a thesis on gasses. When Dr. Kuntz accepted a position at the University of Wuerzburg, Germany, he persuaded Dr. Roentgen to go with him. In Wuerzburg he could not find work, so he tried his luck in two other cities. Eventually the Institute of Physics at the Wuerzburg University did offer him the coveted professorial chair, which he accepted, and in 1888 Professor Roentgen was elected Chancellor of the University. He taught during the day and spent many evenings experimenting in his lab.

On the evening of November 8, 1895, while experimenting with electric current flow, using a spark conductor, he generated high voltages in a partially evacuated glass tube. The tube began to glow. He noticed that crystals of barium platino cyanide scattered on the table began to give off light when the tube glowed. An experienced researcher, he knew he was on to something. Further tests showed that paper, wood, aluminum and some other materials were transparent to these strange rays. Even at a distance of 2 meter the rays were still penetrating a wooden door. The professor realized that he was dealing with invisible electro-magnetic rays, which under certain conditions could stimulate certain materials to fluorescence. He exposed everything he could think of to these strange new rays, among them his weight box, a wire coil in a box and many different materials. He worked like a man possessed and he even slept in his lab. He found that lead glass is permeable to light but not to these rays, while wood stopped the light, but the rays passed through it. Then his thoughts turned towards bones. The bones seemed to screen the surrounding tissues. This monumental discovery enabled man to look inside the human body for the first time.

Dr. Roentgen was uncertain of the nature of his findings, so he called this phenomena " X-Rays ". He took a highly systematic approach to his studies and his experiments. He published a paper about the discovery and in December 1895 he held a demonstration with his first X-Ray pictures, along with one of his wife's hand. The discovery caused much excitement in scientific and medical communities throughout the world. Scientists in many countries started to experiment with these new rays, and progressive doctors very quickly used them as a diagnostic tool. A colleague, Dr. Kollicker, suggested in January 1896 to call these new rays after its discoverer. So it was done in Germany, a doctor orders a Roentgen picture, which is taken in the Roentgen Department of the hospital------- to this day.

During the next decades it became obvious that X-Rays caused injury to various human tissue and to vision. Radioactivity was at that time not being related to these new rays. Many researchers developed radiation burns and cancer; more than 100 people died. These tragedies led to greater awareness of radiation hazards for health care workers. Early in the new century X-Ray equipment was being encased, and lead barriers and lead aprons were being introduced after the hazards became known. All this eventually led to a new branch of science: Radiobiology.

In 1900 Professor Roentgen accepted a position at the University of Munich. One year later he received the first Nobel Prize for Physics for his discovery of X-Rays in Stockholm, Sweden. When his parents died, he inherited 2 million marks, which elevated him to the upper classes in the young German Empire. He traveled extensively with his wife to Italy and France, but most often they spent their vacation in Switzerland. He had fame and wealth and a feudal hunting lodge, but Dr. Roentgen was never really happy in Munich. He spent very little time furthering his research.

Early in the century tuberculosis was still rampant. X-Ray examinations in mobile units throughout Germany detected the disease early and prevented it from spreading. Soon X-Rays were widely used in medicine, industry and scientific research. It became an important tool in the fight against cancer in the form of radiation therapy, along with surgery and chemotherapy. Today computer tomography is used in medicine and material testing. Since the 1960's X-Ray TV has enabled surgeons to monitor their operations. In the mid 70's micro-electronics entered the field of radiography. Today botanists use computer tomography to examine trees for disease, and archaeologists to examine fossils, relics, artifacts and monuments.

Dr. Roentgen once took an X-Ray picture of his gun. Perhaps he had a sense of things to come. One can hardly imagine airport security today without X-Rays. It is still the only devise that will detect an object of potential danger in luggage or on someone's person.

X-Rays are not only generated here on earth; the universe has been full of X-Rays for billions of years. On June 1, 1990 an X-Ray satellite was launched to explore the structure and the developments of planets and the stars of the heavens.

Dr. Roentgen's wife, Bertha, died in 1919 after a lengthy illness, during which he had virtually lived isolated in Munich. War and inflation had eroded his small fortune. Wilhelm Konrad Roentgen died four years later, on February 10, 1923 in Munich at the age of 78. His monumental discovery made a considerable contribution to the welfare of mankind. It also helps to unravel the secrets of nature he had loved so well.

This article was written by Ursula Grosser Dixon R.N., a novice historian.

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