THE PEKCEPTION OF SPACE. (IV.)

533 try to bisect such a line we place the point of division about T V of its length too high. 1 Similarly, a square cross, or a square, drawn on paper, should look higher than it is broad. And that this is actually the case, the reader may verify by a glance at Fig. 23. Fig. 23. For analogous reasons the upper and lower halves of the letter S, or of the figure 8, hardly seem to differ. But when turned upside down, as g, 8> ^ ne upper half looks much the larger. 2 Hering has tried to explain our exaggeration of small angles in the same way. We have more to do with right angles than with any others. Consequently obtuse and acute ones, equally liable to be the images of right ones foreshortened, particularly easily revive right ones in memory. It is hard to look at such figures as a, &, c, in Fig. 24, without seeing Fig. 24. a 7 1 Bulletins de VAcademie de Belgique, 2me Serie, xix. 2. 2 "Wundt seeks to explain all these illusions by the relatively stronger " feeling of innervation" needed to move the eyeballs upwards, a careful study of the muscles concerned is taken to prove this, and a consequently greater estimate of the distance traversed. It suffices to remark, however, with Lipps, that were the innervation all, a column of S's placed on top of each other should look each larger than the one below it, and a weather-cock on a steeple gigantic, neither of which is the case. Only the halves of the same object look different in size, because the customary correction for fore- shortening bears only on the relations of the parts of special things spread out before us. Cp. W. Wundt, Physiol Psych., 2te Ann., ii. 96-8 ; Th. Lipps, Grundtatsachen t &c., p. 535.