The patient attempt to copy mountain-form had made him sensitive to harmony of line; and in the great composers of Florence and Venice he found a quality of abstract design which tallied with his experience of what was beautiful in Nature.

Aiguilles and glaciers, drawn as he drew them, and the figure-subjects of severe Italian draughtsmen, are beautiful by the same laws of composition, however different the associations they suggest.
But _he_ had been learning these laws of beauty from Turner and from the Alps; how did the ancients come by them?
This could be found only in a thorough study of their lives and times, to begin with, to which he devoted his winter, with Rio and Lord Lindsay and Mrs.Jameson for his authorities.

He found that his foes, Caspar Poussin and Canaletto, and the Dutch landscapists, were not the real old masters; that there had been a great age of art before the era of Vandyck and Rubens--even before Michelangelo and Raphael; and that, towards setting up as a critic of the present, he must understand the past out of which it had grown.

So he determined to go to Florence and Venice, and to study the religious painters at first hand.
Mountain-study and Turner were not to be dropped.

For example, to explain the obvious and notorious licences which Turner took with topography, it was necessary to see in what these licences consisted.