Harding had tried to show him how to generalize foliage; but in this example he saw that not generalization was needed to get its beauty, but truth.
At Fontainebleau soon after, in much the same circumstances, a study of an aspen-tree, idly begun, but carried out with interest and patience, confirmed the principle.

At Geneva, once more in the church where he had formed such resolutions the year before, the desire came over him with renewed force; now not only to be definitely employed, but to be employed in the service of a definite mission, which was, in art, exactly what Carlyle had preached in every other sphere of life in that book of "Heroes": the gospel of sincerity.
The design took shape.

At Chamouni he studied plants and rocks and clouds, not as an artist to make pictures out of them, nor as a scientist to class them and analyze them; but to learn their aspects and enter into the spirit of their growth and structure.

And though on his way home through Switzerland and down the Rhine he made a few drawings in his old style for admiring friends, they were the last of the kind that he attempted.

Thenceforward his path was marked out; he had found a new vocation.