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Laureate Rontgen

posted Dec 29, 2014, 11:54 PM by Ranmini Perera   [ updated Jul 19, 2019, 4:15 PM by Upali Salpadoru ]

Fig.1 William Conrad Rontgen .

1845 – 1923  


He discovered "Rontgen rays" named as 

X' rays.

  A lonely man in a darkened room was investigating cathode rays. He obstructed the path of rays leading to a fluorescent holding a plate of lead. What appeared on the screen was a part of a skeleton.  

   Through fear and wonder he decided to keep it a secret. He must have either attributed it to an apparition or suspected himself to be loony.

 In Germany, it all began like this. Cathode rays are the rays coming out of the negative electrode when a charge of several kilo volts is given to the electrodes. The electrodes are separated by a partial vacuum. In the year 1895 on the 8th of November evening Roentgen handled a unit similar to this.

Fig.1 Plan of the cathode ray tube used. CRT.

 Cathode rays that come out to the Aluminium window are shown by the dotted lines. The whole unit was covered with black paper to prevent any stray light coming out.. The aluminum was covered with a thick black paper. Roentgen darkened the room; switched on the unit. There was no chance of any rays coming out. To his utter amazement something glittered on a table a meter away. He looked round. Light was not coming from anywhere...  When he switched off the unit, the glow disappeared. The glowing material was some crystals of a fluorescent salt. (Barium platinocyanide) which he kept to test the cathode rays.  He could not understand how rays could have come out of the tube. But the glowing occurred every time he switched on the CRT.

 He suspected some unknown kind of rays to be coming out of the tube. After getting the rays to travel through objects he obtained the shadows on photographic plates. As the rays seem to be different to what was known at the time he called them X’ rays. He understood the nature of these rays to some extent. and  produced a report after 50 days.

Fig 2 - A simple  X’ ray tube to illustrate the function.

Fig 2 shows how X’ rays are produced. When the cathode rays strike a hard metal such as tungsten, they emit X’ rays. In the original experiment the aluminium would have produced the X’ rays. Fig. 3  below , which  was the first X’ray photograph of a human part is the hand of Mrs.Rontgen. The flesh has been more transparent to rays than the bones. A ring in the finger has not allowed many rays to pass through.

Fig 3 - The hand of Mrs. Rontgen.First X’Ray photograph.of a human part.
Fig 4 - An X-ray picture (radiograph) taken by Röntgen of Albert von Kölliker's hand

 Rontgen was born in the Lower Rhine Province in Germany as the only child of his parents. His father was a clothes manufacturer. His mother, Charlotte came from Netherlands. He received his primary education in Amsterdam. He never showed any special abilities to learn in his childhood or youth but he loved to walk through the forests and climb hills. As a boy he used to dabble in mechanical gadgets. His love for mechanics made him select a Technical School in Utrecht, Unfortunately he could not stay there for long as he was accused of some mischief which he did not commit.In 1865 he entered the Polytechnic at Zurich, passed the exams there and following extra lessons and obtained a PhD from the University of Zurich.  In 1867 he became a lecturer and later a professor at Strasbourg University. After occupying the Chair of Physics at The University of Gleason he changed over to University of Wurzberg, He declined offers from many Universities but due to a special request from the Bavarian Government he joined the University of Munich in 1900 and remained there for the rest of his life.

 William Conrad Roentgen became extremely popular after his discovery of X rays. The public used his name as ‘Rontgen rays’. And ‘Rontgenogram” for the penetrating rays and the impressions recorded respectively.  In Germany and some other countries, some streets and institutions were named after him. Many honors, honorary doctorates, and Membership of exclusive academic circles were thrust upon him. Yet he never lost his common touch or the love of nature. He never had any valets or assistants but most of his instruments he used for experiments were entirely made by him.

 Swedish Academy of Sciences awarded him the very first Nobel Prize in Physics in 1901. “"in recognition of the extraordinary services he has rendered by the discovery of the remarkable rays subsequently named after him". He preferred the rays to be called X’rays. The cash that came with the prize he donated to his University.

Spending vacations in his summer house he roamed about the Bavarian Alps and climbed mountains. .He entertained friends and lived an easy life. Yet no genteel lady would come to his laboratory as they thought Roentgen rays would make them appear naked. “Dirty, dirty Roentgen rays” they used to chant.

Unfortunately late in his life he developed a cancer in his bowels. This could not have been due to the rays, as he had been always behind a lead screen when using rays. He died in Munich on February 10th of 1923. His discoveries will be remembered for ever as they opened up diagnostic medicine and the gateway to understanding of matter.