This is a biographical book. The old world is very remote from us now, but it is worth while making a small attempt to realize how it stood to Wagner. When he was born, in 1813, Bach had been dead only a little over sixty years; Mozart had been dead about twenty years, and Haydn about ten; Beethoven was in the full splendour of his tremendous powers; Weber and Schubert had still their finest work to do. To grasp all that this means, let us consider our relation to Mendelssohn. He died nearly sixty years ago; yet, whatever we may think of him as a composer, we can scarcely call him old-fashioned: he remains indisputably one of the moderns. Now, Wagner can never have looked upon Bach as a modern. He spoke of him and his old periwig almost as one might allude to an extinct race of animals. The history of an art cannot be measured off in years: in some periods it moves slowly, in others with startling rapidity. Since Mendelssohn's day composers have sought rather to develop old resources and forms than to find and create new ones, whereas in the sixty years that lie between Bach's death and Wagner's birth the whole form and content, the very stuff, of music was changed. In 1750 he would have been a daring and extraordinarily sapient being who prophesied that within forty years Mozart's G minor Symphony would be written. Between Bach and Wagner is a great gulf set, a gulf bridged by Emanuel Bach, Haydn, Mozart, and Beethoven; between ourselves and Mendelssohn there is no such chasm and certainly no such list of mighty names.