Chopin schooled his pupils most assiduously and carefully in the Nocturnes as well as in the Concertos of Field, who was, to use Madame Dubois’s words, “an author very sympathetic to him.”  Mikuli relates that Chopin had a predilection for Field’s A flat Concerto and the Nocturnes, and that, when playing the latter, he used to improvise the most charming embellishments.  To take liberties with another artist’s works and complain when another artist takes liberties with your own works is very inconsistent, is it not?  But it is also thoroughly human, and Chopin was not exempt from the common failing.  One day when Liszt did with some composition of Chopin’s what the latter was in the habit of doing with Field’s Nocturnes, the enraged composer is said to have told his friend to play his compositions as they were written or to let them alone.  M. Marmontel writes:—­

Either from a profound love of the art or from an excess of conscience personelle, Chopin could not bear any one to touch the text of his works.  The slightest modification seemed to him a grave fault which he did not even forgive his intimate friends, his fervent admirers, Liszt not excepted.  I have many a time, as well as my master, Zimmermann, caused Chopin’s sonatas, concertos, ballades, and allegros to be played as examination pieces; but restricted as I was to a fragment of the work, I was pained by the thought of hurting the composer, who considered these alterations a veritable sacrilege.

This, however, is a digression.  Little need be added to what has already been said in another chapter of the third composer of the group we were speaking of.  Chopin, the reader will remember, told Moscheles that he loved his music, and Moscheles admitted that he who thus complimented him was intimately acquainted with it.  From Mikuli we learn that Moscheles’ studies were very sympathetic to his master.  As to Moscheles’ duets, they were played by Chopin probably more frequently than the works of any other composer, excepting of course his own works.  We hear of his playing them not only with his pupils, but with Osborne, with Moscheles himself, and with Liszt, who told me that Chopin was fond of playing with him the duets of Moscheles and Hummel.

Speaking of playing duets reminds me of Schubert, who, Gutmann informed me, was a favourite of Chopin’s.  The Viennese master’s “Divertissement hongrois” he admired without reserve.  Also the marches and polonaises a quatre mains he played with his pupils.  But his teaching repertoire seems to have contained, with the exception of the waltzes, none of the works a deux mains, neither the sonatas, nor the impromptus, nor the “Moments musicals.”  This shows that if Schubert was a favourite of Chopin’s, he was so only to a certain extent.  Indeed, Chopin even found fault with the master where he is universally regarded as facile princeps.  Liszt remarks:—­