‘Cosi fan tutte,’ his next work, was produced at Vienna in January, 1790.  It has never been so successful as its two predecessors, chiefly on account of its libretto, which, though a brisk little comedy of intrigue, is almost too slight to bear a musical setting.  The plot turns upon a wager laid by two young officers with an old cynic of their acquaintance to prove the constancy of their respective sweethearts.  After a touching leave-taking they return disguised as Albanians and proceed to make violent love each one to the other’s fiancee.  The ladies at first resist the ardent strangers, but end by giving way, and the last scene shows their repentance and humiliation when they discover that the too attractive foreigners are their own lovers after all.  There is much delightful music in the work, and it is greatly to be regretted that it should have been so completely cast into the shade by ’Le Nozze di Figaro,’

Mozart’s next opera, ‘La Clemenza di Tito,’ was hastily written, while he was suffering from the illness which in the end proved fatal.  The libretto was an adaptation of an earlier work by Metastasio.  Cold and formal, and almost totally devoid of dramatic interest, it naturally failed to inspire the composer.  The form in which it was cast compelled him to return to the conventions of opera seria, from which he had long escaped, and altogether, as an able critic remarked at the time, the work might rather be taken for the first attempt of budding talent than for the product of a mature mind.  The story deals with the plotting of Vitellia, the daughter of the deposed Vitellius, to overthrow the Emperor Titus.  She persuades her lover Sextus to conspire against his friend, and he succeeds in setting the Capitol on fire.  Titus, however, escapes by means of a disguise, and not only pardons all the conspirators, but rewards Vitellia with his hand.  The opera was produced at Prague on the 6th of September, 1791, and the cold reception which it experienced did much to embitter the closing years of Mozart’s life.

‘Die Zauberfloete,’ his last work, was written before ’La Clemenza di Tito,’ though not actually produced until September 30, 1791.  The libretto, which was the work of Emanuel Schikaneder, is surely the most extraordinary that ever mortal composer was called upon to set.

At the opening of the opera, the Prince Tamino rushes in, pursued by a monstrous serpent, and sinks exhausted on the steps of a temple, from which three ladies issue in the nick of time and despatch the serpent with their silver spears.  They give Tamino a portrait of Pamina, the daughter of their mistress, the Queen of Night, which immediately inspires him with passionate devotion.  He is informed that Pamina has been stolen by Sarastro, the high-priest of Isis, and imprisoned by him in his palace.  He vows to rescue her, and for that purpose is presented by the ladies with a magic flute, which will keep him safe in every danger,