UNDER THE APPLE-TREES 
life must everywhere be essentially the same, and 
hence that life is not possible on the major and minor 
planets unless, or until, conditions upon them are 
similar to those upon the earth. But what astro- 
nomic significance would the fact have if life never 
appeared upon any of the other planets, nor upon 
any of the bodies that swarm in celestial space? 
None whatever. The vast celestial mechanism 
would know it not. Doubtless there are untold 
worlds where life has never appeared and never will 
appear, and other untold worlds upon which it has 
appeared and has run its course, or is now in full 
career. 
The natural philosophers tell us that under a cer- 
tain size a planet cannot retain an atmosphere; it 
drifts away to the larger and more powerful bodies. 
Probably our moon has never had an atmosphere. 
They also tell us that a world with a very small par- 
ticle of radium in its rocky interior, — two parts ina 
million million parts, — like our earth, must inevi- 
tably, in the course of time or of eternity, explode. 
This may be what happened to the body of which 
the four hundred asteroids are fragments. 
What a comfort, a sort of cosmic comfort, it 
would be to us dwellers upon this astronomic mote, 
to have positive proof that there were beings like 
ourselves upon other astronomic motes in the heav- 
ens around us, even if we had to know that millions 
of them were trying desperately to exterminate each 
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