A HISTORY OF 



he expected a very unequal surface, to be 

 smooth and even. He was then shown a mi- 

 niature-picture of his father, which was con- 

 tained in his mother's watch-case, and he rea- 

 dily perceived the resemblance; but asked, 

 with great astonishment, how so large a face 

 could be contained in so small a compass? 

 It seemed as strange to him as if a bushel was 

 contained in a pint vessel. At first he could 

 bear but a very small quantity of light, and 

 he saw erery object much greater than the 

 life ; but, in proportion as he saw objects that 

 were really large, he seemed to think the for- 

 mer were diminished ; and although he knew 

 the chamber where he was contained in the 

 house, yet, until he saw the latter, he could 

 not be brought to conceive how a house could 

 be larger than a chamber. Before the ope- 

 ration, he had no great expectations from the 

 pleasure he should receive from a new sense; 

 he was only excited by the hopes of being 

 able to read and write ; he said, for instance, 

 that he could hare no greater pleasure in 

 walking in the garden with his sight, than he 

 had without it, tor he walked there at his ease, 

 and was acquainted with all the walks. He 

 remarked also, with great justice, that his for- 

 mer blindness gave him one advantage over 

 the rest of mankind, which was that of being 

 able to walk in the night with confidence and 

 security. But when he began to make use 

 of his new sense, he seemed transported be- 

 yond measure. He said, that every new ob- 

 ject was a new source of delight, and that his 

 pleasure was so great as to be past expres- 

 sion. 



About a year after, he was brought to Ep- 

 som, where there is a very fine prospect, with 

 which he seemed greatly charmed ; and he 

 called the landscape before him a new me- 

 thod of seeing. He was couched in the other 

 eye, a year after the former, and the opera- 

 tion succeeded equally well : when he saw 

 with both eyes, he said that objects appear- 

 ed to him twice as large as when he saw but 

 with one; however, he did not see them dou- 

 bled, or, at least, he showed no marks as if 

 he saw them so. Mr. Cheselden mentions in- 

 instances of many more that were restored to 

 sight in this manner ; they all seemed to con- 

 cur in their perceptions with this youth ; and 

 all seemed particularly embarrassed in 



learning how to direct their eyes to the ob 

 jects they wished to observe. 



In this manner it is that our feeling correct; 

 the sense of seeing, and that objects which 

 appear of very different sizes at different dis- 

 tances, are all reduced, by experience, to 

 their natural standard. " But not the feeling 

 only, but also the colour and brightness ot 

 the object, contributes, in some measure, to 

 assist us in forming an idea of the distance at 

 which it appears." Those which we see most 

 strongly marked with light and shade, we rea- 

 dily know to be nearer than those on which 

 the colours are more faintly spread, and that, 

 in some measure, take a part of their hue from 

 the air between us and them. Bright objects 

 also are seen at a greater distance than such 

 as are obscure, and, most probably, for this 

 reason, that being less similar in colour, to 

 the air which interposes, their impressions are 

 less effaced by it, and they continue more dis- 

 tinctly visible. Thus a black and distant ob- 

 ject is not seen so far off" as a bright and glit- 

 tering one, and a fire by night is seen much 

 farther off" than by day." 



The power of seeing objects at a distance 

 is very rarely equal in both eyes. When this 

 inequality is in any great degree, the person 

 so circumstanced then makes use only of one 

 eye, shutting that which sees the least, and 

 employing the other with all its power. And 

 hence proceeds that awkward look which is 

 known by the name of strabism. 



There are many reasons to induce us to 

 think that such as are near-sighted see objects 

 larger than other persons ; and yet the con- 

 trary is most certainly true, for they see them 

 less. Mr. Buffbn informs us that he himself 

 is short-sighted, and that hisleft eyeisstronger 

 than his right. He has very frequently expe- 

 rienced, upon looking at any object, such as 

 the letters of a book, that they appear less to 

 the weakest eye; and that when he places the 

 book, so as that the letters appear double, 

 the images of the left eye, which is strongest, 

 are greater than those of the right, which is 

 the most feeble. He has examined several 

 others, who were in similar circumstances, and 



a Mr. Buffon gives a different theory, for which I must 

 refer the reader to the original. That I have given, I 

 take to be easy and satisfactory enough. 



