NEW PLUMS AND PRUNES 151 



Thus we are told that the smallest particle of 

 matter visible under the magnifying influence of 

 the most powerful microscope is of such dimen- 

 sions that 50,000 of such particles placed in line 

 would be required to cross the space of one cen- 

 timeter or about two-fifths of an inch. If we 

 calculate the cube of this number we find that 

 125 thousand billion such particles could be 

 crowded into the space of a cubic centimeter. But 

 it further appears that, according to a definite 

 measurement made by Professor Rutherford, 

 more than 20 bi^'on times that number of helium 

 atoms would exist in the form of gas in the same 

 space. 



And the commentator I am quoting adds: 

 "Of course the molecules of gas are widely sep- 

 arated. So it follows that the smallest particle 

 of solid matter visible through the most power- 

 ful microscope contains many times 20 billion 

 atoms." 



"Many times 20 billion atoms" in the smallest 

 particle of matter that the microscope reveals! 

 Vastly more than that number of atoms, then, 

 in each individual chromosome of the group 

 lying within the nuclei of pollen grain and ovule 

 since these are by no means at the limits of 

 visibility. And each atom has itself specific in- 

 dividuality. Each group of a thousand atoms 



