His method of painting was deliberate; a little added to-day, something more another day; the whole process extending, frequently, over several years. For the feeling which he wished to express was a very subtle one, so the living growth of it, as of many things in nature, was slow. On the other hand, most of the great painters seem to have been swift workers; or at any rate their final result gives one the impression of having been executed in the vigor and glow of a swiftly working mind.