They are not to be reckoned as equals; for Lionardo and Michelangelo outstrip the other two almost as much as these surpass all lesser craftsmen.

Each of the four men expressed his own peculiar vision of the world with pen, or chalk, or metal point, finding the unique inevitable line, the exact touch and quality of stroke, which should present at once a lively transcript from real Nature, and a revelation of the artist's particular way of feeling Nature.

In Lionardo it is a line of subtlety and infinite suggestiveness; in Michelangelo it compels attention, and forcibly defines the essence of the object; in Raffaello it carries melody, the charm of an unerring rhythm; in Andrea it seems to call for tone, colour, atmosphere, and makes their presence felt.

Raffaello was often faulty: even in the wonderful pen-drawing of two nudes he sent to Albrecht Duerer as a sample of his skill, we blame the knees and ankles of his models.

Lionardo was sometimes wilful, whimsical, seduced by dreamland, like a god born amateur.