I looked the song up on Wikipedia (reliable source that it is) and found the lyrics. Why don't they sing the last part?

Quote Originally Posted by Wikipedia
Well they fought for poor old Ireland, and full bitter was their fate,
Oh what glorious pride and sorrow, fills the name of ninety-eight!
Yet, thank God, e'en still are beating hearts in manhood burning noon,
Who would follow in their footsteps, at the risin' of the moon
By the rising of the moon, By the rising of the moon
Who would follow in their footsteps, at the risin' of the moon.