up, and that on these they must turn the arches, whereon the
woodwork for supporting the weight must rest. Others affirmed that the
vault should be turned in cysteolite or sponge-stone (spugna), thereby
to diminish the weight; and several of the masters agreed in the opinion
that a column must be erected in the centre, and the cupola raised in
the form of a pavilion, like that of San Giovanni in Florence. Nay,
there were not wanting those who maintained that it would be a good plan
to fill the space with earth, among which small coins (quatrini) should
be mingled, that when the cupola should be raised, they might then give
permission that whoever should desire the soil might go and fetch it,
when the people would immediately carry it away without expense. Filippo
alone declared that the cupola might be erected without so great a mass
of woodwork, without a column in the centre, and without the mound of
earth; at a much lighter expense than would be caused by so many arches,
and very easily, without any framework whatever.

"Hearing this, the syndics, who were listening in the expectation of
hearing some fine method, felt convinced that Filippo had talked like a
mere simpleton, as did the superintendents, and all the other citizens;
they derided him therefore, laughing at him, and turning away; they bade
him discourse of something else, for that this was the talk of a fool or
madman, as he was. Therefore Filippo, thinking he had cause of offence,
replied, 'But consider, gentlemen, that it is not possible to raise the
cupola in any other manner than this of mine, and although you laugh at
me, yet you will be obliged to admit (if you do not mean to be
obstinate), that it neither must nor can be done in any other manner;
and if it be erected after the method that I propose, it must be turned
in the manner of the pointed arch, and must be double--the one vaulting
within, the other without, in such sort that a passage should be formed
between the two. At the angles of the eight walls, the building must be
strengthened by the dove-tailing of the stones, and in like manner the
walls themselves must be girt around by strong beams of oak. We must
also provide for the lights, the staircases, and the conduits by which
the rain-water may be carried off. And none of you have remembered that
we must prepare supports within, for the execution of the mosaics, with
many other difficult arrangements; but I, who see the cupola raised, I
ha