The peculiar indistinctness dependent on the retirement of objects from the eye

In the last chapter, we have seen how indistinctness of individual distances becomes necessary in order to express the adaptation of the eye to one or other of them; we have now to examine that kind of indistinctness which is dependent on real retirement of the object, even when the focus of the eye is fully concentrated upon it. The first kind of indecision is that which belongs to all objects which the eye is not adapted to, whether near or far off: the second is that consequent upon the want of power in the eye to receive a clear image of objects at a great distance from it, however attentively it may regard them.

Draw on a piece of white paper a square and a circle, each about a twelfth or eighth of an inch in diameter, and blacken them so that their forms may be very distinct; place your paper against the wall at the end of the room, and retire from it a greater or less distance accordingly as you have drawn the figures larger or smaller. You will come to a point where, though you can see both the spots with perfect plainness, you cannot tell which is the square and which the circle.

Causes confusion, but not annihilation of details.

Now this takes place of course with every object in a landscape, in proportion to its distance and size.