John Hall Wheelock - The Panther

His gaze through the bars forever going by him
Has grown so dulled it takes in nothing else.
To him it seems a thousand bars go by him,
That behind the thousand bars there is nothing else.

The soft tread of those strong and supple paces,
Turning in the smallest circle, round and round,
Is like a dance of strength about a center
In which some mighty will stands stunned and bound.

At times, though, the curtain over the pupil
Will lift. Then an image passes in soundlessly,
Passes through the tense stillness of the limbs-
And in the heart, ceases to be.

John Hall Wheelock

http://www.poemhunter.com/poem/the-panther-4/