Life in England එංගලන්තයේ ජීවිතය
1896 Age 24 yrs. Henry Becquerel discovered some rays, slightly different from X rays, emanating from fluorescent chemicals. While X’ rays were unaffected in a magnetic field ‘Becquerel rays’ got deflected. This discovery triggered the investigations of two great scientists Madam Curie in France and Ernest Rutherford in England.  Fig, 2 Ernest Rutherford adopting Becquerel’s experiment. Rutherford repeated Becquerel’s experiment of analysing ‘Uranium rays’ (as Becquerel called them). Instead of using photographic films to detect the rays he adopted a discovery made by his teacher. Professor Thomson had discovered that gases can be made to conduct electricity when bombarded with certain rays.
In the circuit shown there is a gap between the positive and negative plates preventing a current passing through. When the alpha rays pass through the meter showed a current. Rutherford placed various materials to block rays and tested the penetrating power. He found what Becquerel had suspected to be correct. While some rays could not pass through even a tissue paper others could even pierce a sheet of Aluminium. He named the rays stopped by paper as Alpha and the rays with a high penetrating power as Beta. 1898 Age 26 yrs. Rutherford changed the mode of detecting these rays from the ionization method to a fluoroscope method. He applied Zinc sulphide on aglass plate to detect alpha collisions. 
Fig.2 Rays deviating due to an electric field. He also discovered that the rays could be separated by using two electrically charged plates or by a magnetic field. Alpha rays got slightly attracted to the negative plate while the Beta rays deviated a lot by the positive charge. He found that the Beta rays to be similar to a stream of electrons concluded that alpha particles ought to be much heavier than the electrons. With this discovery he became world famous. On a request made by the McGill University in Canada, Professor J.J. Thomson wrote, “I have never had a student with more enthusiasm or ability for original research than Mr Rutherford and I am sure that if elected he would establish a distinguished school of Physics at Montreal.” Rutherford was not very eager to leave Cambridge and go to Canada. But for the 26 year old lad to get a Research Professorship to work in a highly sophisticated lab, with an annual salary of $ 2,500 p.a., was not an offer to be refused. 1900 Age 28 yrs. Paul Villard in Paris recognised the highly penetrating rays which were similar to X’ rays. They are named as Gamma rays. For the first time in his life, Rutherford got a permanent employment. It was time for him to think of his fiancée. The same year he returned to New Zealand to meet Miss. Mary Newton. Mary and her mother were well known social workers. Soon the wedding bells pealed at Christchurch for Ernest and Mary. 1901 Age 29 yrs. Mary gave birth to a daughter and named her as Eileen Rutherford. Leaving childcare and the household chores to his wife Rutherford worked zealously, along with a few dedicated students, to solve the mystery Marie Curie had named as ‘Radioactivity’. The work he did with a demonstrator Frederick Soddy (1921 Noble laureate) was extremely crucial. They discovered that heavy atoms break down into lighter atoms, contrary to the belief at the time that “atoms are indivisible”. In the meantime he also discovered a new element. This was a radioactive gas which he named as Radon. 1907 Age 35 yrs. Rutherford returned to England and joined Manchester University as a Professor. He started research with a German scientist Dr. Hans Geiger. They passed alpha rays through extremely thin sheets of mica and various other metals using a radioactive gas radon-222 as the source. The rays had to pass inside a partially evacuated tube. It was necessary for them to stay in a dark room for quite some time for the eyes to get adapted to feeble light. They also used an electronic device to count. A remark by Rutherford shows how tedious the job was, “Geiger is a good man and worked like a slave. Our tube worked like a charm… Geiger could count at intervals the whole night.” The deviations they found were extremely small.They thought an alpha particle to get deflected very slightly be each charged particle and the resulting deviation to be the cumulative effect of a large number of such particles. 
. “We didn’t have the money, so we had to think”. Rutherford quoted later in life,
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