Lately we [Robert and Clara Schumann] have been absorbed in your organ sonatas, unfortunately with the piano as substitute; but we should have discovered that they were yours without the name on the cover. They are stamped on every page with that striving after perfection which makes me look to you as my model. Then the poetry and originality of the form! Each sonata is rounded off to a complete picture. Bach’s music gives me the impression of himself seated at the organ. But yours brings me a vision of a Cecilia fingering the keys. How charming that that should be your wife’s name, too! The fifth and sixth struck me as being the most important. One thing is certain, dear Mendelssohn, no one but you writes harmonies so pure, harmonies ever increasing in purity and spiritual beauty. Have I been praising you again? May I?