[Islam-Online- Psychology]

With both eyes focused on the object at K, the point in which the common axis EZ cuts the transverse line HT at right angles:

1	-	The two objects at H and T, and all points on HT, are seen single; the line HT appears as a single line; and
2	-	The line EZ is seen as two lines that intersect at K, and so is each of the diameters AD and BG.

Experiment 2
With the eye fixed on the object at H or at T - a case in which the visual axes are not symmetrically situated with respect to the common axis EZ:

1	-	The objects at H, K, T, and all points on HT, are seen single; the line HT appears as a single line; and
2	-	The line EZ, and each of the diameters AD and BG, are seen double.

Experiment 3
With two objects at L and F on the common axis EZ (=c), before and after K, respectively, and with the eyes focused on K:

1	-	The two objects appear as four - two over to the right, and two over to the left; and
2	-	Each of the four objects (i.e., images) appears on one of the two lines into which has been doubled.

Experiment 4
Three cases are considered:

1	-	With the eyes fixed on K and objects O1 and O2 placed at two points on one of the diameters, then on the other, one object, O1, before, and the other, O2, beyond K: Each of the two objects, and each of the diameters, appears double.
2	-	With the eyes fixed on K, and the objects O1 and O2 placed on the near segments of the diameters: The two objects appear as four - two closer together, and two farther apart.
3	-	With the eyes fixed on K, and the two objects placed on the far segments of the diameters: The two objects appear as four, as in case (2), two closer together and two farther apart.

Experiment 5
The eyes are fixed on the middle object at K while regarding an object placed, first, at a point I beyond H but very close to it, then at a point Q farther away from H - both I and Q being on the right edge of the board: The object appears single when regarded at I, and double when regarded at Q.