Vitruvius on perspective.
Vitruvius, advising proportions of an architrave should vary depending on how high they are relative to the ground (De Architectura 3.5): Quo altius enim scandit oculi species, non facile persecat aëris crebritatem, dilapsa itaque altitudinis spatio et viribus, exstructam incertam modulorum renuntiat sensibus quantitatem. For, given how high the eye’s view is rising, it’s not […]
Also tagged 1st century BC, translation, Vitruvius