Read the poem and answer the question that follows.

I saw three witches
That bowed like barley,
And flew on their brooms in the sky,
They soared on a cloud,
Above with a sound,
Stood black in the silver as they did fly.

I saw three witches
That teased little sparrows,
In cages they carried along,
Till a hawk from above,
Swooped down like an arrow,
And freed all the sparrows, correcting the wrong.

I saw three witches
That sailed on a boat,
All with smiles that were mean,
Till a bank of green trees came
They hid their faces with ease,
Though I heard them laughing, they were not seen.

I saw three witches
Asleep in a valley,
Their heads like pebbles,
And then the moon shone so bright
In the valley that night,
Turned them to bushes, so they wouldn't trouble.

What does the line "correcting the wrong" mean in the second stanza of the poem?