ANIMALS. ."^^.S 



and a long aquaintance with the real size of every object quickly 

 assures us of the distance at which it is seen. The last man in 

 a file of soldiers appears in reality much less, perhaps ten times 

 more diminutive, than the man next to us ; however, we do not 

 perceive this difference, but continue to think him of equal sta- 

 ture ; for the numbers we have seen thus lessened by distance, 

 and have found, by repeated experience, to be of the natural size 

 when we come closer, instantly correct the sense, and every ob- 

 ject is perceived with nearly its natural proportion. But it is other - 

 wise, if we observe objects in such situations as we have not 

 had sufficient experience to correct the errors of the eye ; if, for 

 instance, we look at men from the top of a high steeple, they, 

 in that case, appear very much diminished, as we have not had a 

 habit of correcting the sense in that position. 



Although a small degree of reflection will serve to convince 

 us of the truth of these positions, it may not be amiss to 

 strengthen them by an authority which cannot be disputed. 

 Mr Cheselden having couched a boy of thirteen for a cataract, 

 who had hitherto been blind, and thus at once having restored 

 him to sight, curiously marked the progress of his mind upon 

 chat occasion. This youth, though he had been till then inca- 

 pable of seeing, yet was not totally blind, but could tell day from 

 night, as persons in his situation always may. He could also, 

 with a strong light, distinguish black from white, and either from 

 the vivid colour of scarlet : however he saw nothing of the form 

 of bodies ; and without a bright light, not even colours them- 

 selves. He was at first couched only in one of his eyes ; and 

 when he saw for the first time, he was so far from judging of 

 distances, that he supposed his eye touched every object that he 

 saw, in the same manner as his hands might be said to feel them. 

 The objects that were most agreeable to him were such as were 

 of plain surfaces and regular figures : though he could as yet 

 make no judgment whatever of their different forms, nor give a 

 reason why one pleased him more than another. Although he 

 rould form some idea of colours during his state of blindness, 

 ■yet that was not sufficient to direct him at present ; and he 

 fould scarcely be persuaded that the colours he now saw were 

 the same with those he had formerly conceived such erroneous 

 ideas of. He delighted most in green ; but black objects as if 

 giving him an idea of his lornior blindness, he regarded with 



