She was enabled to give voice to her own emotions, forgetful of the audience for the time being.

And even in subsequent scenes, when the recollection of being a performer returned upon her, her inward excitation seemed to float her onward, like a great wave.
Once again her own feelings took her up, like a tornado, and made her seem a wonderful actress.

In the scene where Norma is tempted to kill her children, she fixed her indignant gaze full upon Fitzgerald, and there was an indescribable expression of stern resolution in her voice, and of pride in the carriage of her queenly head, while she sang: "Disgrace worse than death awaits them.

Slavery?
No! never!" Fitzgerald quailed before it.

He grew pale, and slunk back in the box.