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COSMOLOGY : OLD AND NEW
blage of electrons, protons and neutrons in different numbers Uranium, a metal element, is radio-active. Radio-activity has nothing to do with radio broadcasting. It is a technical term which expresses a peculiar property of certain metals. Uranium emits, day and night, unceasingly three kinds of rays which are denoted by Greek names, alpha, beta and gamma. Alpha rays are streams of particles which are the nucleii of Helium atoms. Beta rays are streams of electrons; and gamma rays are the rays of the nature of light. When an atom of uranium loses three alpha particles it is converted into an atom of radium." The atom of radium is again radio-active, i.e., it emits day and night the same three kinds of rays. When one atom of radium loses five alpha particles it is converted into the metallic lead.
This is a confirmation of one part of the definition of pudgala. This shows the dissociative (गलयन्ति)
AWURANIUM character of pudgala dravya, one form of matter changing into another form by the separation of
W RADIUM electrons and protons. In the adjoining figure is given the full chain of radio-active changes in uranium.
In confirmation of the above series of changes in uranium metal it may be mentioned that there (The chain shows the formation exist, in the earth's crust, rocks of different substances by the which are rich in uranium. Radio
adin
separation separation
1"
pur) of alpha
and beta particles from within active disintegration, i.e., the
the atoms. the circles of diffebreaking up of atoms by the emis- rent sizes show the relative sion of alpha and beta rays, is weights of the different subsunceasingly proceeding in these tances formed.) rocks. Geological researches have
Fig. 4 shown that the end-product viz. lead metal is always found
114. Radium is the cost liest met al on earth, the present price being about Rs. 3,00,000 per tola. It is being successfully used in the treatment of cancer of the heart and other deadly diseases of the skin. Recently it has been replaced by cobalt 60.