other two doors
of S. Giovanni, a very ancient temple, indeed, the oldest in that city;
and they ordained among themselves that instructions should be sent to
all the masters who were held the best in Italy, to repair to Florence
in order that their powers might be tested by a specimen scene in
bronze, similar to one of those which Andrea Pisano had formerly made
for the first door.

Word of this determination was written to Lorenzo, who was working at
Pesaro, by Bartoluccio, urging him to return to Florence in order to
give a proof of his powers, and saying that this was an occasion to make
himself known and to demonstrate his genius, not to mention that he
might gain such profit that neither the one nor the other of them would
ever again need to labour at making ear-rings.

The words of Bartoluccio stirred the spirit of Lorenzo so greatly, that
although Signor Pandolfo, with all his Court and the other painter, kept
showing him the greatest favour, Lorenzo took leave of that lord and of
the painter, and they, with great unwillingness and displeasure, allowed
him to go, neither promises nor increase of payment availing to detain
him, since to Lorenzo every hour appeared a thousand years until he
could return to Florence. Having departed, therefore, he arrived safely
in his own city. Many foreigners had already assembled and presented
themselves to the Consuls of the Guild, by whom seven masters were
elected out of the whole number, three being Florentines and the others
Tuscans; and it was ordained that they should have an allowance of
money, and that within a year each man should finish a scene in bronze
by way of test, of the same size as those in the first door. And for the
subject they chose the story of Abraham sacrificing his son Isaac,
wherein they thought that the said masters should be able to show their
powers with regard to the difficulties of their art, seeing that this
story contained landscapes, figures both nude and clothed, and animals,
while the foremost figures could be made in full-relief, the second in
half-relief, and the third in low-relief.

The competitors for this work were Filippo di Ser Brunellesco, Donato,
and Lorenzo di Bartoluccio, all Florentines; Jacopo della Quercia of
Siena, and Niccolo d'Arezzo, his pupil; Francesco di Valdambrina; and
Simone da Colle, called Simone de' Bronzi. All these men promised
before the Consuls that they would deliver their scenes finished within
the said