Bewick published the first edition of the British Quadrupeds in 1790, the first edition of the first volume of the British Birds in 1797, and of the second volume in 1804; all these became popular, and were several times republished with additional cuts. His other works were very numerous, but, as a whole, they are of inferior value. Both in the volumes which have been mentioned and in his later work he received much aid from his pupils, who designed and engraved, subject to his correction and approval, many illustrations which are ascribed to him. In his own work, notwithstanding his great excellence, he was by no means perfect. In delineating rocks and the bark of trees, especially, he fails; in drawing he sometimes makes errors, particularly when what he represents was not subject to direct and frequent observation; in the knowledge of line-arrangement, too, he is less masterly than some of his successors, and, in this respect, his work is characterized by effectiveness and spirit rather than by finish. Yet, when these deductions have been made from his merit, so much remains as to render him, without doubt, the most distinguished modern engraver in wood. [Illustration: FIG. 68.--The Sheep-fold. By Blake. From Virgil’s Pastorals.] [Illustration: FIG. 69.--The Mark of Storm. By Blake. From Virgil’s Pastorals.] Before Bewick’s death, in 1828, another English genius, William Blake (1758-1827), greater as an artist than as an engraver, produced a series of woodcuts (Fig. 68) which is remarkable for vigor and originality. They were published in a reprint of Ambrose Philips’s Imitation of Virgil’s First Eclogue, in Dr. Thornton’s curious edition of Virgil’s Pastorals which appeared in 1820. One of them (Fig. 69) represents a landscape swept by violent wind. The idea of autumnal tempest has seldom been so strikingly and forcibly embodied as in the old gnarled oak straining with laboring limbs, the hedge-rows blown like indistinguishable glimmering dust, the keen light of the crescent moon shining through the driving storm upon the rows of laid corn and over the verge of the distant hill. Contemporary engravers said the series was inartistic and worthless, and an uneducated eye can easily discover faults in it; imaginative genius of the highest order is expressed in it, nevertheless, and from this the series derives its value. Blake never made a new trial of the art.