the longer. Hence, as
the line of sight to the upper part is the longer, it makes that part
look as if it were leaning back. But when the members are inclined to
the front, as described above, they will seem to the beholder to be
plumb and perpendicular.

14. Each column should have twenty-four flutes, channelled out in such a
way that if a carpenter's square be placed in the hollow of a flute and
turned, the arm will touch the corners of the fillets on the right and
left, and the tip of the square may keep touching some point in the
concave surface as it moves through it. The breadth of the flutes is to
be equivalent to the enlargement in the middle of a column, which will
be found in the figure.

15. In the simae which are over the coronae on the sides of the temple,
lion's heads are to be carved and arranged at intervals thus: First one
head is marked out directly over the axis of each column, and then the
others are arranged at equal distances apart, and so that there shall be
one at the middle of every roof-tiling. Those that are over the columns
should have holes bored through them to the gutter which receives the
rainwater from the tiles, but those between them should be solid. Thus
the mass of water that falls by way of the tiles into the gutter will
not be thrown down along the intercolumniations nor drench people who
are passing through them, while the lion's heads that are over the
columns will appear to be vomiting as they discharge streams of water
from their mouths.

In this book I have written as clearly as I could on the arrangements of
Ionic temples. In the next I shall explain the proportions of Doric and
Corinthian temples.

BOOK IV

INTRODUCTION

1. I have observed, Emperor, that many in their treatises and volumes of
commentaries on architecture have not presented the subject with
well-ordered completeness, but have merely made a beginning and left, as
it were, only desultory fragments. I have therefore thought that it
would be a worthy and very useful thing to reduce the whole of this
great art to a complete and orderly form of presentation, and then in
different books to lay down and explain the required characteristics of
different departments. Hence, Caesar, in my first book I have set forth
to you the function of the architect and the things in which he ought to
be trained. In the second I have discussed the supplies of material of
which buildings are constructed. In the