UNDER THE APPLE-TREES 
molecular physics the molecules and atoms and 
electrons are self-moved, and are in perpetual mo- 
tion. If the Brunonian movement extended to 
visible ponderable bodies, the earth would be un- 
inhabitable; we should behold a sight such as we 
have never yet beheld. Spontaneous motion never 
takes place among inanimate bodies, while it is the 
rule among the atoms of which they are composed. 
Gravity and friction bind the bodies on the surface 
of the earth, but these laws are inoperative in the 
world of atoms and electrons. On the other hand, 
when we reach the astronomic world, or the sidereal 
universe, we find the same condition that prevails in 
the world of the infinitely little: perpetual motion 
goes on, friction is abolished, and nothing is at rest; 
there are collisions and disruptions just as there are 
in the world of atoms. Height and depth, upper and 
under, east and west, north and south, weight and 
inertia, as we experience them, have vanished. 
There are no boundaries, no ending and no begin- 
ning, no centre and no circumference; the infinite 
cannot have any of these. Rest and motion are rela- 
tive terms. The sun is at rest with reference to the 
earth, but in motion with reference to some larger 
system, which is again at rest when tried by the sun. 
Motion implies something which is not in motion. 
The bodies we know have weight with reference 
to the earth, as the earth has with reference to 
some larger body, and this again with reference to 
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