About the same time Lodovico Gonzaga, Marquis of Mantua, wished to build the tribune and the principal chapel in the Nunziata, the Church of the Servi in Florence, after the design and model of Leon Batista; and pulling down a square chapel, old, not very large, and painted in the ancient manner, which stood at the head of the church, he built the said tribune in the bizarre and difficult form of a round temple surrounded by nine chapels, all curving in a round arch, and each within in the shape of a niche. Now, since the arches of the said chapels rest on the pilasters in front, the result is that the stone dressings of the arches, inclining towards the wall, tend to draw ever backwards in order to meet the said wall, which turns in the opposite direction according to the shape of the tribune; wherefore, when the said arches of the chapels are looked at from the side, it appears that they are falling backwards, and that they are clumsy, as indeed they are, although the proportions are correct, and the difficulties of the method must be remembered. Truly it would have been better if Leon Batista had avoided this method, for, although there is some credit for the difficulty of its execution, it is clumsy both in great things and in small, and it cannot have a good result. And that this is true of great things is proved by the great arch in front, which forms the entrance to the said tribune; for, although it is very beautiful on the outer side, on the inner side, where it has to follow the curve of the chapel, which is round, it appears to be falling backwards and to be extremely clumsy. This Leon Batista would perhaps not have done, if, in addition to science and theory, he had possessed practical experience in working; for another man would have avoided this difficulty, and would have rather aimed at grace and greater beauty for the edifice. The whole work is otherwise in itself very beautiful, bizarre, and difficult; and nothing save great courage could have enabled Leon Batista to vault that tribune in those times in the manner that he did. Being then summoned by the same Marquis Lodovico to Mantua, Leon Batista made for him the models of the Church of S. Andrea and of some other works; and on the road leading from Mantua to Padua there may be seen certain temples built after his manner. Many of the designs and models of Leon Batista were carried into execution by Salvestro Fancelli, a passing good architect and sculptor of Florence, who, according to the desire of the said Leon Batista, executed with judgment and extraordinary diligence all the works that he undertook in Florence. For those in Mantua he employed one Luca, a Florentine, who, living ever afterwards in that city and dying there, left his name—so Filarete tells us—to the family of the Luchi, which is still there to-day. It was no small good-fortune for him to have friends who understood him and were able and willing to serve him, because architects cannot be always standing over their work, and it is of the greatest use to them to have a faithful and loving assistant; and if any man ever knew it, I know it very well by long experience.
In painting Leon Batista did not do great or very beautiful works, for the few by his hand that are to be seen do not show much perfection; nor is this to be wondered at, seeing that he devoted himself more to his studies than to draughtsmanship. Yet he could express his conceptions well enough in drawing, as may be seen from some sketches by his hand that are in our book, in which there are drawn the Bridge of S. Angelo and the covering that was made for it with his design in the form of a loggia, for protection from the sun in summer and from the rain and wind in winter. This work he was commissioned to execute by Pope Nicholas V, who had intended to carry out many similar works throughout the whole of Rome; but death intervened to hinder him. There is a work of Leon Batista's in a little Chapel of Our Lady on the abutment of the Ponte alla Carraja in Florence—namely, an altar-predella, containing three little scenes with some perspectives, which he was much more able to describe with the pen than to paint with the brush. In the house of the Palla Rucellai family, also in Florence, there is a portrait of himself made with a mirror; and a panel with rather large figures in chiaroscuro. He also made a picture of Venice in perspective, with S. Marco, but the figures therein were executed by other masters; and this is one of the best examples of his painting that there are to be seen.
Leon Batista was a person of most honest and laudable ways, the friend of men of talent, and very open and courteous to all; and he lived honourably and like a gentleman—which he was—through the whole course of his life. Finally, having reached a mature enough age, he passed content and tranquil to a better life, leaving a most honourable name behind him.