Inquisitors, indeed, continued to be regularly appointed, and to perform such of their functions as they could, but the decline in their usefulness is shown by one of the earliest acts of Martin V., in 1417, before leaving Constance, in commissioning the Observantine Franciscan, Giovanni da Capistrano, as a special inquisitor against the heretics of Mantua. From this time, in fact, when any effective effort against heresy was called for, the regular machinery of the Inquisition was no longer relied upon. It seems to have been regarded as effete for all the purposes for which it had been instituted, and special appointments were necessary of men devoted to the work, such as Capistrano and his friend Giacomo della Marca. Just as the inquisitorial jurisdiction had superseded the episcopal, so now both were overslaughed as insufficient. Thus, in 1457, when a new heresy sprang up in Brescia and Bergamo concerning Christ, the Virgin, and the Church Militant, infecting both clergy and laity, and including suspicion of sorcery, Calixtus III. ordered his nuncio in those parts, Master Bernardo del Bosco, to seize the heretics and try them, with even more than the privileges of an inquisitor, for he was empowered to proceed to final judgment and execution without appeal, leaving it to his discretion whether he should call for advice upon the inquisitors and episcopal ordinaries. Two years later, in the case of Zanino da Solcia, to which I shall recur hereafter, the sentence was rendered by the Lombard inquisitor, Frà Jacopo da Brescia, but the examination took place in the presence of Master Bernardo del Bosco, who moreover received the abjuration of Zanino, and the sentence was sent to Pius II. and was modified by him. The diminution of popular respect for the Inquisition was still further manifested in 1459, by the doubts publicly expressed of the validity of the bulls of Innocent IV. and Alexander IV. authorizing inquisitors to preach crusades against heretics and to prosecute for heresy all persons and communities impeding them, so that Calixtus III. was obliged to reissue the authorization.[303]