THE THEORY OF ELECTRONS 



An atom of matter is composed of electrons. We picture an atom as 

 a sort of miniature solar system, the electrons (particles of negative 

 electricity rotating round a central nucleus of positive electricity, as 

 described in the text. In the above pictorial representation of an atom 

 the whirling electrons are indicated in the outer ring. Electrons move 

 with incredible speed as they pass from one atom to another. 



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ARRANGEMENTS OF ATOMS IN A DIAMOND 



The above it a model (seen from two points of view) of the arrangement of the atoms in a 

 diamond. The arrangement it found by studying the X-ray spectra of the diamond. 



