The ancient architects ...... beginning with the Egyptians (?) who,
as Diodorus Siculus writes, were the first to build and construct
large cities and castles, public and private buildings of fine form,
large and well proportioned .....

The column, which has its thickness at the third part .... The one
which would be thinnest in the middle, would break ...; the one
which is of equal thickness and of equal strength, is better for the
edifice. The second best as to the usefulness will be the one whose
greatest thickness is where it joins with the base.

[Footnote: See Pl. CIII, No. 3, where the sketches belonging to
lines 10--16 are reproduced, but reversed. The sketch of columns,
here reproduced by a wood cut, stands in the original close to lines
5--8.]

The capital must be formed in this way. Divide its thickness at the
top into 8; at the foot make it 5/7, and let it be 5/7 high and you
will have a square; afterwards divide the height into 8 parts as you
did for the column, and then take 1/8 for the echinus and another
eighth for the thickness of the abacus on the top of the capital.
The horns of the abacus of the capital have to project beyond the
greatest width of the bell 2/7, i. e. sevenths of the top of the
bell, so 1/7 falls to the projection of each horn. The truncated
part of the horns must be as broad as it is high. I leave the rest,
that is the ornaments, to the taste of the sculptors. But to return
to the columns and in order to prove the reason of their strength or
weakness according to their shape, I say that when the lines
starting from the summit of the column and ending at its base and
their direction and length ..., their distance apart or width may be
equal; I say that this column ...