30 TWO NEW WORLDS 



with us, but the ratio of available forces to masses 

 is also increased 10 22 times, so that the balance is 

 preserved. For forces are reduced only 10 33 times, 

 while masses are reduced 10 55 times. 



Handling and moving " objects" in the infra- world 

 will be much the same as with us. The work per 

 volume will be much greater, the play of energy 

 more intense ; but this is just what we should expect 

 at such a very high rate of existence. Life in the 

 infra-world is strenuous to an extent we little dream 

 of. And yet, since the means available are commen- 

 surate to the ends, there is no essential difference. 



The span of life is proportional to the scale of time 

 and space. Even on our own earth there is a rough 

 proportionality between the length of the body of an 

 animal and the length of its normal span of life. 

 For this there is a physiological reason. Life is 

 essentially a succession of nerve pulses, of actions 

 and reactions, between the sentient self and the 

 external world through the medium of the physical 

 organism. Each such interaction consists of an 

 impulse travelling inwards from without, and an 

 answering impulse travelling outwards from within. 

 These impulses are transmitted by the nerves at a 

 certain rate depending upon certain physical pro- 

 perties of the transmitting substance. The rate of 

 transmission is comparatively slow. It is about 3000 

 cm. per second. Therefore, an interval of about a 

 tenth of a second must elapse between two succes- 



