[361] Physiol. Optik, p. 741.
[362] Hermann's Handbuch, iii, i, 548.
[363] Helmholtz: Tonempfindungen, 3d ed. 85-9 (Engl. tr., 2d ed. 50, 51; see also pp. 60-1).
[364] Physiol. Psych., ii, 209.
[365] Physiol. Optik, 741.
[366] P. 728.
[367] Popular Scientific Lectures, Eng. Trans., p. 295.
[368] Similarly in the verses which some one tried to puzzle me with the other day: "Gui n'a beau dit, qui sabot dit, nid a beau dit elle?"
[369] I cannot refrain from referring in a note to an additional set of facts instanced by Lotze in his Medizinische Psychologie, § 431, although I am not satisfied with the explanation, fatigue of the sense-organ, which he gives. "In quietly lying and contemplating a wall-paper pattern, sometimes it is the ground, sometimes the design, which is clearer and consequently comes nearer.... Arabesques of monochromic many-convoluted lines now strike us as composed of one, now of another connected linear system, and all without any intention on our part. [This is beautifully seen in Moorish patterns; but a simple diagram like Fig. 39 also shows it well.
