Niccola Pisano founded a school. His son Giovanni, and the numerous pupils employed upon the monuments just mentioned at Siena, Bologna, and Perugia, carried on the tradition of their master, and spread his style abroad through Italy. Giovanni Pisano, to whom we owe the Spina Chapel and the Campo Santo at Pisa, the façade of the Sienese Duomo, and the altar-shrine of S. Donato at Arezzo--four of the purest works of Gothic art in Italy--showed a very decided leaning to the vehement and mystic style of the Transalpine sculptors. We trace a dramatic intensity in Giovanni's work, not derived from his father, not caught from study of the antique, and curiously blended with the general characteristics of the Pisan school. In spite of the Gothic cusps introduced by Niccola into his pulpits, the spirit of his work remained classical. The young Hercules holding the lion's cub in his right hand upon his shoulder, while with his left he tames the raging lioness, has the true Italian instinct for a return to Latin style. The same sympathy with the past is observable in the self-restraint and comparative coldness of the bas-reliefs at Pisa. The Junonian attitude of Madonna, the senatorial dignity of Simeon, the ponderous folding of the drapery, and the massive carriage of the neck throughout, denote an effort to revivify an antique manner. What, therefore, Niccola effected for sculpture was a classical revival in the very depth of the Middle Ages. The case is different with his son Giovanni. Profiting by the labours of his father, and following in his footsteps, he carried the new art into another region, and brought a genius of more picturesque and forcible temper into play. The value of this new direction given to sculpture for the arts of Italy, especially for painting, cannot be exaggerated. Without Giovanni's intervention, the achievement of Niccola might possibly have been as unproductive of immediate results as the Tuscan Romanesque, that mediaeval effort after the Renaissance, was in architecture.[62]