In perspective drawing, as a mental altitude, the viewer's eye-level is the horizon, struggling with the various forces that inform our understanding or perception of a place.
Earth's radius is between 6357 km (polar) and 6378 km (equatorial) - one meter used to be defined as one ten-millionth of the length of the meridian from pole to the equator.
So, you can calculate the distance to the horizon by multiplying 113 times the square root of the altitude (perspective drawing).
Drawing in perspective has a unique angle that sets you apart from the competition.
Still, a very nice thing to write about.
It does not prove that we stand now where the early Byzantines stood, with the ruins of a civilisation clattering about our ears and our eyes set on a new horizon (Clive Bell). Art is a signalling system using patterns and pattern recognition for human communication.
A Times critic argues that ours is the least innovative century for the arts in 500 years. That doesn’t have to be a bad thing.