Chopin's 24 Preludes, Op. 28, are a set of short pieces for the piano, one in each of the twenty-four keys, originally published in 1839. Chopin wrote them between 1835 and 1839, partly at Valldemossa, Majorca, where he spent the winter of 1838-39 and where he had fled with George Sand and her children to escape the damp Paris weather. In Majorca, Chopin had a copy of Bach's The Well-Tempered Clavier, and as in each of Bach's two sets of preludes and fugues, his Op. 28 set comprises a complete cycle of the major and minor keys, albeit with a different ordering. The autograph manuscript, which Chopin carefully prepared for publication, carries a dedication to the German pianist and composer Joseph Christoph Kessler. The French edition was dedicated to the piano-maker and publisher Camille Pleyel, who had commissioned the work for 2,000 francs (equivalent to nearly $30,000 in present day).