CHAPTER III 



LIFE IN THE INFRA-WORLD 



1. WE have seen that if orbital motions resembling 

 the earth's motion round the sun are to be pre- 

 served on a molecular scale the scale of the infra- 

 world and if the absolute orbital velocities arc 

 to be of the same order in each case, centripetal 

 forces must be at work which greatly exceed the 

 gravitational force we are accustomed to. Such 

 a centripetal force, enormous in comparison with 

 gravitational force, we are already familiar with 

 in the case of electrostatic attraction. When one 

 electron is placed at a distance of 1 cm. from another, 

 it repels it with a force of about 10~ 19 dynes. By 

 virtue of their ponderable masses, the two electrons 

 at the same time attract each other with a force 

 of about 10" 62 dynes. In this case, therefore, the 

 electric force exceeds the gravitational force 10 43 

 times. This enormous difference shows at once that 

 as soon as electric forces come into play we are 

 amply provided with machinery for producing the 

 necessary speed of revolution. But it has been 

 objected that such prodigious forces as these would 

 break up any structure with which we are acquain 



