tions of his building with reference to a
certain part selected as the standard. After the standard of symmetry
has been determined, and the proportionate dimensions adjusted by
calculations, it is next the part of wisdom to consider the nature of
the site, or questions of use or beauty, and modify the plan by
diminutions or additions in such a manner that these diminutions or
additions in the symmetrical relations may be seen to be made on correct
principles, and without detracting at all from the effect.

2. The look of a building when seen close at hand is one thing, on a
height it is another, not the same in an enclosed place, still
different in the open, and in all these cases it takes much judgment to
decide what is to be done. The fact is that the eye does not always give
a true impression, but very often leads the mind to form a false
judgment. In painted scenery, for example, columns may appear to jut
out, mutules to project, and statues to be standing in the foreground,
although the picture is of course perfectly flat. Similarly with ships,
the oars when under the water are straight, though to the eye they
appear to be broken. To the point where they touch the surface of the
sea they look straight, as indeed they are, but when dipped under the
water they emit from their bodies undulating images which come swimming
up through the naturally transparent medium to the surface of the water,
and, being there thrown into commotion, make the oars look broken.

3. Now whether this appearance is due to the impact of the images, or to
the effusion of the rays from the eye, as the physicists hold, in either
case it is obvious that the vision may lead us to false impressions.

4. Since, therefore, the reality may have a false appearance, and since
things are sometimes represented by the eyes as other than they are, I
think it certain that diminutions or additions should be made to suit
the nature or needs of the site, but in such fashion that the buildings
lose nothing thereby. These results, however, are also attainable by
flashes of genius, and not only by mere science.

5. Hence, the first thing to settle is the standard of symmetry, from
which we need not hesitate to vary. Then, lay out the ground lines of
the length and breadth of the work proposed, and when once we have
determined its size, let the construction follow this with due regard to
beauty of proportion, so that the beholder may feel no doubt of the
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