Opera was also a refuge from the tensions of the age. The light genres of opera - comic operas and simple farces - were in particular demand. At the beginning of XIX century the absolute ruler of European theatrical life was Gioachino Rossini (1792-1868). Italian opera reigned supreme at the time: Italian singers were the industry's superstars, Italian impresarios worked in theatres outside Italy and local composers tried to create something resembling Rossini's delightful fireworks of opera buffa.
https://www.youtube.com/watch?v=LfiaQtO53M4
Rossini also wrote serious operas and they were a resounding success in their day. However, in the modern repertoire there have survived primarily funny operas with their comic personas, easy assemblage construction (it was common practice to use in one opera the music of another if it was superfluous) and proven ways to make the listener laugh. These still work brilliantly, like the comic tongue-in-cheek, or the hilarious confusion that makes the audience and the characters dizzy, all at progressively higher volume, as if a confetti cannon were about to burst.
https://www.youtube.com/watch?v=CNmt3QwOSF8
The opera had number structure.
(it consisted of arias and ensembles with clear beginnings and endings) - specially so that applause would rage between them. The main dramatic engine was the cantabile-cabal system.
"cantabile - cabaletta" system - The pensive slow aria cantabile (followed by a sparkling cabaletta with a simple, bouncy rhythm. In between there were sections of parlando - "spoken in chant".
They introduced slow arias and allowed the characters to naturally 'switch' from them to fast ones. While at the beginning of the century the virtuoso cabaletta was the main hobby of the soloist-singer, in the operas of the 1830s and 1840s the emphasis shifted to the slow cantabile. The art of magical, soaring, sweet Italian singing was mastered by singers over decades of inhuman labour. For the first months one had to do only silent throat exercises; then for several years one had to sing only scales, achieving a perfect evenness of tone. This is bel canto (it. 'beautiful singing'), and in this sense we can call the art of Italian singers in general, including the Baroque era.
But it is the operas of the early nineteenth century, and of the Rossinian, and especially the tragic operas of Italian composers a generation younger, that can be referred to as 'bel canto operas'. In these dramas of love and madness, which are usually set in remote, poetically gloomy locales, the characters perform the same cantabile that serve as symbols of opera for the public in general. Beautiful as the sweetest reverie, the arias bring us to tears, and more than compensate for the clumsiness and absurdity inherent in the plots of these operas.
https://www.youtube.com/watch?v=4XMs7paGx-o
By the way: one of bel canto's finest operas, Gaetano Donizetti's Lucia di Lammermoor, has a reference
"madness scene" of the protagonist. It is so impressive and perfect that it has become canon. After Lucia a whole string of operatic heroines by various authors have raved and hallucinated onstage in her image.
Notes:
Belcanto - In the field of vocal art - the mastery of Italian opera singers. As applied to the history of music - designation of the style inherent in Italian operas of the first third of the 19th century.
Cantabile - slow aria.
Cabaletta - A moving and bravura aria in a volitional, rhythmic character.
See also:
Gioachino Rossini, Gaetano Donizetti, Vincenzo Bellini