This gave legitimate occasion to the Florentines to undertake operations against them; so leaving Serezana they encamped before Pietra Santa, which was very populous, and made a gallant defense.  The Florentines planted their artillery in the plain, and formed a rampart upon the hill, that they might also attack the place on that side.  Jacopo Guicciardini was commissary of the army; and while the siege of Pietra Santa was going on, the Genoese took and burned the fortress of Vada, and, landing their forces, plundered the surrounding country.  Biongianni Gianfigliazzi was sent against them, with a body of horse and foot, and checked their audacity, so that they pursued their depredations less boldly.  The fleet continuing its efforts went to Livorno, and by pontoons and other means approached the new tower, playing their artillery upon it for several days, but being unable to make any impression they withdrew.

In the meantime the Florentines proceeded slowly against Pietra Santa, and the enemy taking courage attacked and took their works upon the hill.  This was effected with so much glory, and struck such a panic into the Florentines, that they were almost ready to raise the siege, and actually retreated a distance of four miles; for their generals thought that they would retire to winter quarters, it being now October, and make no further attempt till the return of spring.

When the discomfiture was known at Florence, the government was filled with indignation; and, to impart fresh vigor to the enterprise, and restore the reputation of their forces, they immediately appointed Antonio Pucci and Bernardo del Neri commissaries, who, with vast sums of money, proceeded to the army, and intimated the heavy displeasure of the Signory, and of the whole city, if they did not return to the walls; and what a disgrace, if so large an army and so many generals, having only a small garrison to contend with, could not conquer so poor and weak a place.  They explained the immediate and future advantages that would result from the acquisition, and spoke so forcibly upon the subject, that all became anxious to renew the attack.  They resolved, in the first place, to recover the rampart upon the hill; and here it was evident how greatly humanity, affability, and condescension influence the minds of soldiers; for Antonio Pucci, by encouraging one and promising another, shaking hands with this man and embracing that, induced them to proceed to the charge with such impetuosity, that they gained possession of the rampart in an instant.  However, the victory was not unattended by misfortune, for Count Antonio da Marciano was killed by a cannon shot.  This success filled the townspeople with so much terror, that they began to make proposals for capitulation; and to invest the surrender with imposing solemnity, Lorenzo de’ Medici came to the camp, when, after a few days, the fortress was given up.  It being now winter, the leaders of the expedition thought it unadvisable to make any further effort until the return of spring, more particularly because the autumnal air had been so unhealthy that numbers were affected by it.  Antonio Pucci and Biongianni Gianfigliazzi were taken ill and died, to the great regret of all, so greatly had Antonio’s conduct at Pietra Santa endeared him to the army.