Wild guess: the song refers to a dead person, and "Big Blue" is "heaven" or "the hereafter" or "death".

Judging merely by the heading, I thought the thread was about IBM. Emotion: stick out tongue
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That makes sense, MrP. Thank you.

But do you think your interpretation goes well with the entire lyrics? You said the song refered to a dead person, but I thought it's about the purity which can be particularly found among children and which we adults have forgotten; it seemed that 'dark chest of wonder' represented such purity.

What do you think?
My best guess is: the one in the Big Blue (the child flying through the sky) is what the world stole from me (i.e., innocence).
That makes much better sense, davkett!!
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TakaThat makes much better sense, davkett!!

("It's time to cut the rope and fly" seems to be a balloon metaphor.)