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National Resources Planning Board 



the neutrons can be used to disintegrate more uranium 

 atoms, which in turn will give out neutrons, the process 

 wiJl be continuous and the heat produced may be used 

 as a source of power. The only question is whether 

 enough neutrons can be produced to keep the reaction 

 going continuously. The evidence here is not yet 

 conclusive, and while it looks as if there are not quite 

 enough neutrons produced to obtam power, it is pos- 

 sible that such power could be obtained by the splitting 

 of other atoms. Thus, while a few years ago, the ques- 

 tion of the obtaiumg of power from the energy bound 

 up in the atoms was only discussed speculatively in 

 popular scientific magazines, it has now become a very 

 important practical question to the physicist. It has 

 been calculated that if a method of this kind can be 

 worked out, it will be possible to obtain power at a 



considerably lower cost than it is now obtained from 

 coal. 



Study of the Solid State 



The physicist has also been busy studying the outer 

 structure of atoms. By means of the spectroscope he 

 has been able to identify many atoms by the color of 

 the light they emit. Using this color he can in turn 

 discover the number of electrons and their arrangement 

 in the outer structure of the atoms. Until recently his 

 knowledge was restricted to atoms which were widely 

 separated as in gases. Calculations have now been 

 made to determine the forces that act between atoms 

 and thus hold them together in solids. Such calcula- 

 tions have allowed the elastic properties, the density, 

 and the heats of vaporization of very simple metals 



FiGDBE 77. — Viscosimeter for Dctertnination of the Absolute Viscosity of Glass, Owens-Illinois Glass Company, Toledo, Ohio 



