The stereoscope

by David Brewster

[8] These angles are equal in this diagram and in the vision of a sphere, but they are inequal in other bodies.

[9] Aguilonius, Opticorum, lib. ii. book xxxviii. pp. 140, 141.

[10] It is obvious that a complete hemisphere is not seen with both eyes.

[11] Aguilonius, Opticorum, lib. iv. pp. 306, 307.

[12] In the last of these theorems Aguilonius describes and explains, we believe for the first time, the conversion of relief in the vision of convex and concave surfaces. See Prop. xciv. p. 312.

[13] Id., p. 313.

[14] Opera, tom. ii. p. 394. Lugduni, 1658.

[15] Opera Mathematica Optica, tribus libris exposita, p. 136.

[16] Opticks, vol. ii., Remarks, pp. 41 and 245.

[17] Id., vol. i. p. 48, Fig. 196.