Bright ball of flame that through the gloom of even
Silently takest thine aethereal way,
And with surpassing glory dimm'st each ray
Twinkling amid the dark blue depths of Heaven,--
Unlike the fire thou bearest, soon shalt thou
Fade like a meteor in surrounding gloom,
Whilst that, unquenchable, is doomed to glow
A watch-light by the patriot's lonely tomb;
A ray of courage to the oppressed and poor;
A spark, though gleaming on the hovel’s hearth,
Which through the tyrant’s gilded domes shall roar;
A beacon in the darkness of the Earth;
A sun which, o'er the renovated scene,
Shall dart like Truth where Falsehood yet has been.

Percy Bysshe Shelley

http://www.poemhunter.com/poem/sonnet-to-a-balloon-laden-with-knowledge/