Poem: Why are bubbles round?

1
Bubbles are round because Mother Earth
And the moon are round,

Because the sea-tumbled grey and green pebbles
Are round, and the clock,

Compass, sextant, disk, L.E.D.,
And ring of fire, are round.

2
Bubbles are round because water molecules
Are attracted downward and inward,

Creating a fragile skin of surface tension
That cradles water like a baby.

3
Bubbles are round because tension
Draws the water into its most compact shape

And the most compact shape—
On this planet—is a ball.
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