MIRACLES OF SCIENCE 



of times smaller than the atom. To make the com- 

 parison vivid, Becquerel likens the electrons in an 

 atom to a swarm of gnats gravitating about in the 

 dome of a cathedral. 



THE STRUCTURE OF THE ATOM 



Some imaginative physicists think of the electrons 

 as making up planetary systems within the atom, and 

 as circling about with infinite speeds in orbits differ- 

 ing only in their infinitesimal smallness from the 

 orbits of planets and stars of the visible universe. 

 Other physicists caution us against drawing too close 

 analogies between the stellar and atomic systems. 

 But all are agreed that the activities of the electron, 

 whether thought of as orbital or as vibratory, are 

 enormous. 



Sir J. J. Thomson estimates that an electron once 

 dislodged from its atomic system, may dash hither 

 and thither from one atom to another at such speed 

 as to change its location forty million times in a 

 second. 



Be that as it may, the demonstration seems com- 

 plete that the activities of the electron and these 

 alone produce the manifestations of energy which 

 we interpret as light, radiant heat, and electricity. 

 All chemical action is likewise held to be due to the 

 activities of the electron. It is suspected that gravi- 

 tation is of the same origin. 



The electron which thus seems to be responsible 

 for all manifestations of energy, is regarded by many 

 physicists as the sole constituent of matter. Dif- 

 ferent kinds of atoms, in this view, differ from one 



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