THE JOURNEYING ATOMS 



after the fox has passed! The all but infinite divi- 

 sibility of matter is proved by every odor that the 

 breeze brings us from field and wood, and by the 

 delicate flavors that the tongue detects in the food 

 we eat and drink. But these emanations and solu- 

 tions that affect our senses probably do not repre- 

 sent a chemical division of matter; when we smell 

 an apple or a flower, we probably get a real frag- 

 ment of the apple, or of the flower, and not one or 

 more of its chemical constituents represented by 

 atoms or electrons. A chemical analysis of odors, 

 if it were possible, would probably show the ele- 

 ments in the same state of combination as the sub- 

 stances from which the odors emanated. 



The physicists herd these ultimate particles of 

 matter about; they have a regular circus with them; 

 they make them go through films and screens; they 

 guide them through openings; they count them as 

 their tiny flash is seen on a sensitized plate; they 

 weigh them; they reckon their velocity. The alpha- 

 rays from radio-active substances are swarms of tiny 

 meteors flying at the incredible speed of twelve 

 thousand miles a second, while the meteors of the 

 midnight sky fly at the speed of only forty miles a 

 second. Those alpha particles are helium atoms. 

 They are much larger than beta particles, and have 

 less penetrative power. Sir J. J. Thomson has de- 

 vised a method by which he has been able to photo- 

 graph the atoms. The photographic plate upon 

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