Equally remarkable is the Arno landscape in the Martyrdom of St. Sebastian, Figure 108, which was painted in 1475. It has the defects of an experimental and academic performance, is a show piece. The executioners are even repeated, to show both front and rear aspects. All the same, its power is impressive and beyond the range of any artist then living, with the possible exception of Piero della Francesca. In painting Pollaiuolo’s accomplishment is so even, and in draped figures so ugly, that we may well pass the series of Virtues which with his brother Piero he did in 1469 for the Mercantile Court, and consider his great engraving known as the Ten Nudes, Figure 109, the odd decorative disposition of which is imitated by Botticelli in the Allegory of Spring; and the fresco of Dancing Men, in which Pollaiuolo successfully vies with the convivial and Bacchic themes of the Greek vase painters. The group is odd and effective as pattern, and inspired by a joyous energy. Painting only claimed a fraction of Antonio’s effort; often he merely made the sketch and left the execution to his rather tame brother, Piero. At the end of his life he was called down to Rome to make the bronze tomb for Sixtus IV. There he died in the year 1498, being sixty-three years old. While his own achievement was somewhat cramped and limited, he had made the most valuable contributions to the art, or rather to the science of painting. He had inspired a titan like Signorelli and a poet like Botticelli, and in certain aspects Leonardo da Vinci and Michelangelo only continued and perfected his work. As late as Benvenuto Cellini’s day his sketches were passed about the studios for the instruction of young painters in anatomy. [Illustration: FIG. 109. Antonio Pollaiuolo. Fighting Men—“The Ten Nudes.” Engraving. ] A kindred strenuous spirit, Piero della Francesca,[42] affords an interesting contrast to Pollaiuolo. Though an Umbrian, he belongs spiritually to Florence. For Piero the world was a frozen thing. He investigated with utmost zeal the mathematical basis of perspective, producing on that topic a laborious and quite unreadable book. He studied anatomy and construction in light and dark, and all the atmospheric problems therewith associated. To attain atmospheric envelopment, he sacrificed color. His pictures exist in silvery grays, suggesting the blondness and tonal unity of modern open-air painting. The drama of life never engrossed him. His world is passionless and almost motionless, coldly impressive. Although he practiced all refinements of modelling, he never made those relaxations of contour which suggest movement. His figures are finely constructed and beautifully placed but emotionally unrelated. They merely exist rather splendidly, as do some of Manet’s figures. Indeed the warning of George Moore as regards Manet applies equally to Piero. It is futile to seek from him anything but fine painting. [Illustration: