to say, in the foreground—are largest; the things in the middle, or middle distance, are smallest. And to explain these apparently simple facts we must exerecise our wits.
You know that when you stand on the seashore and look seaward the extent of your vision is bounded by the meeting of the sea and sky, which boundary is called the horizon. The horizon is the line that follows the line of your eyes, the boundary line. The word is derived form the Greek horos, a limit or boundary.
When you stand on the beach and look at the sea your level position is low, and your horizon is low, because it is on a level with your eyes.
But climb the cliffs and turn seaward; the horizon is the level of your eyes.
Ascend to the very top of the cliffs. Now you are high indeed. Look again toward the horizon; it has extended; again it is the height of your eyes.
The line of the horizon is not always visible because of intervening objects, but as the horizon is the height of the artist's eye its position must be clearly understood, and indicated—for a time at least—in your drawings.
It is possible that you are still unconvinced. Perhaps you live in a city where roofs and houses block a distant horizon from view. Then we may apply another illustration and explain matters differently.
Suppose you descend to the street in a lift and look up at the buildings. What do you see? Every window, every cornice and roof, coming down to the level of your eye.
Now take the lift to the top story of your tall building. What do you then see? Everything is reversed. The eaves of each lower building, the roofs and cornices, rising to meet the level of your eye.
And the level of your eye is the height of your horizon.
"Is the thing below the level of my eye, or is it above the level of my eye?" is the inevitable question.