THE POINT OF HEIGHT IS A POINT AT THE HEIGHT OF THE EYE PERPENDICULAR TO THE GROUND LINE.

When it concerns the point of height, it must be at the same distance from the visible thing, and as for its height, it must always be at the height of a man's eye; this is about five feet. But because a man could be on a mountain, or because it will sometimes be necessary to see into a courtyard or garden or other thing for which it will be necessary to elevate the said point higher, such that its elevation will be at discretion, but for indifferent things, one must rather make it five feet or thereabouts.

---

IGNOGRAPHY IS THE BASE OR FLOOR PLAN OF THE VISIBLE THING.

Before making any foreshortened figure, we must know the height, length, and width of all lengths and widths, if one is to make a plan of it, which the Greeks call ignography ground plan.

---

ORTHOGRAPHY IS ALL THE HEIGHTS OF THE VISIBLE THING THAT ONE WISHES TO PUT INTO FORESHORTENING.

The other plan, called orthography elevation by the Greeks, is an elevation of the visible thing above the ground line.

---

SCENOGRAPHY IS THE FORESHORTENING OF THE VISIBLE THING.

Scenography perspective projection, that is to say, the description of scenes or theaters, has been so called by the Greeks because, as Marcus Vitruvius says, Book 7, Chapter 5, the Greeks—the first inventors of the arts, and from whom we retain the names—feigned with their paintings various sorts of columns against the walls and counterfeited the scenes, of which there were three sorts: tragic, comic, and satiric. Since then, everything that has been foreshortened by reasons of perspective is named scenography, as one can still see in the same Author, Book One, Chapter two.