One of the most interesting forms in this collection is that shown in Fig. 10 (a). This young man sees only 1 and 0 distinctly; 2 and 9 stand in their proper places, but are less distinct;

Fig. 10.	Fig. 11.⁠

while 3 and 8 are seen but faintly in a shadowy form. The intervening figures are not seen at all, but the appropriate space for them is there. His alphabet form accompanying discloses the

Fig. 12.	Fig. 13.⁠

same principle. A, m, n, and s are very distinct; b and y are fainter; c and x are shadowy; a blank space intervenes, sufficient for the other letters. This young man has a brother and two sis-