More significant still are the words which Weber wrote to Fran von Chezy when she was writing the libretto for "Euryanthe;" which he intended to make better than all his previous works. "When you begin to elaborate the text," he wrote; "I entreat you by all that is sacred to task me with the most difficult kinds of metre, unexpected rhythms, etc., which will force my thoughts into new paths and draw them out of their hiding-places." In one of his theoretical essays, Wagner emphasizes the value of a good poem in kindling the spark of inspiration in a composer's mind by exclaiming: "Oh, how I adore and honor Mozart because he found it impossible to compose for his 'Titus' as good music as for his 'Don Juan,' or for his 'Cosi fan Tutte' as good music as for 'Figaro.'" Mozart, he adds, always wrote music, but _good_ music he could only write when he was inspired, and when this inspiration was supplied by a subject worthy of being wedded to his muse. No doubt Wagner was right in maintaining that Mozart's operas contain his best music. Where among all his purely instrumental works is anything to be found as inspired as the music in the scenes where the ghostly statue nods at _Don Juan_, and subsequently where it enters his room and clutches his hand in its marble grasp? I venture to add that even Beethoven, although he is not generally regarded as an operatic composer _par excellence_, and although his fame chiefly rests on his symphonies and other instrumental works, nevertheless composed his most inspired music in connection with his one opera "Fidelio." I refer to the third "Leonora" overture, and to the music in the prison scene, where the digging of the grave is depicted in the orchestra with a realism worthy of Wagner, and where the music when _Leonora_ levels her pistol at the villain reaches a climax as thrilling as is to be found in any dramatic work, musical or literary. Obviously, it was the intensely dramatic situation which here inspired Beethoven to the grandest effort of his genius.