non credea mirarti / Sì presto estinto, o fiore ("I did not believe I would see you fade so soon, oh flower") from Amina's final aria is inscribed on Bellini's tomb in the Catania Cathedral in Sicily.

Then Bellini experienced the re-occurrence of an illness which had emerged in Venice due to pressure of work and the bad weather, and which consistently recurred after each opera.

That Pasta owned a house near Como and would be staying there over the summer was the reason that Felice Romani traveled to meet both her and Bellini.

By 15 July they had decided on a subject for early 1831, but it was uncertain as to whether Pasta was interested in singing a trousers role, that of the protagonist, Ernani, in an adaptation of Victor Hugo's Hernani, later set to music by Giuseppe Verdi in 1844.

With both men having various other commitments, by the end of November 1830 nothing had been achieved in the way of writing either the libretto or the score of Ernani[4] but, by January, the situation and the subject had changed.

Bellini wrote that "[Romani] is now writing La sonnambula, ossia I Due Fidanzati svezzeri...It must go on stage on 20 February at the latest.

[11] Later, it was a vehicle for showcasing Jenny Lind, Emma Albani and—in the early 20th century—for Lina Pagliughi and Toti Dal Monte.

Stagings were presented as frequently as every two years in one European or North American venue or another, and they continued through the 1950s bel canto revivals up to the publication of his book in 1971.

[11] The opera was rescued from the ornamental excesses and misrepresentations more similar to the baroque style than the bel canto of Bellini when it was sung by Maria Callas in the now-famous 1955 production by Luchino Visconti at La Scala.

[15] Scene 1: A village, a mill in the background As the betrothal procession of Amina and Elvino approaches, the villagers all proclaiming joy for Amina, Lisa, the proprietress of the inn, comes outside expressing her misery: Tutto è gioia, tutto è festa...Sol per me non non v'ha contento / "All is joy and merriment...

Elvino arrives, exclaiming Perdona, o mia diletta / "Forgive me my beloved", and explaining that he had to stop on his way at his mother's grave to ask her blessing on Amina.

The newcomer, who surprises the villagers by his familiarity with the locality, asks about the celebrations and admires Amina, who reminds him of a girl he had loved long ago.

(Tu non sai con quei begli occhi / come dolce il cor mi tocchi / "You can't know how those dear eyes gently touch my heart, what adorable beauty".)

Realising that her nocturnal wanderings have given rise to the story of the village phantom, Rodolfo is about to take advantage of her helpless state.

Amina continues her sleepwalk and falls asleep on the sofa, but Rodolfo hears the sound of people approaching and, with no other way out, he climbs out of the window.

Elvino is not convinced and takes back the ring, though he is unable to tear her image from his heart: (Aria, then chorus: Ah!

As they are about to go to the church, Rodolfo enters and tries to explain that Amina is innocent because she did not come to his room awake – she is a somnambulist, a sleepwalker: (Duet, first Elvino Signor Conte, agli occhi miei / negar fede non poss'io / "I cannot deny, my lord, what my eyes have seen"; then Rodolfo V'han certuni che dormendo / "Certain people when they sleep go about as if awake".)

Elvino refuses to believe him and calls upon Lisa to leave, but at that moment Teresa begs the villagers to be quiet, because Amina has at last fallen into an exhausted sleep.

Elvino demands proof and Rodolfo, seeing the sleeping Amina walking across the high, dangerously unstable mill bridge, warns that to wake her would be fatal.

non giunge uman pensiero / al contento ond'io son piena / "Human thought cannot conceive of the happiness that fills me".