Chap. IT.] Inflexion of Light. 295 



Another knife was then placed oppofite to the for- 

 mer, and he obferved, that when the ciiftance of their 

 edges was about the four hundredth part of an inch, 

 the ftream divided in the middle, and left a fhadow 

 between the two pares, which was fo dark, that all 

 light palling between the knives feemed to be bent 

 afide to one knife or the other; as the knives were 

 brought nearer to each other, this fhadow grew broad- 

 er, till upon the contact of the knives the whole light 

 difappeared. 



Purfuing his obfervado'ns upon this appearance, he 

 perceived fringes, as they may be termed, of different 

 coloured light, three made on one fide by the edge of 

 one knife, and three on the other fide by the edge of 

 the other, and thence concluded, that as in refraction 

 the rays of light are differently acted upon, fo are they 

 at a diftance from bodies by inflection ; and by many 

 other experiments of the fame kind he fupported his 

 pofition, which is confirmed by all fubfequent experi- 

 ments. 



We may naturally conclude, that from this property 

 -of inflection fome curious changes will be produced 

 in the appearances of external objects. If we take a 

 piece of wire of a lefs diameter than the pupil of the 

 eye, and place it between the eye and a diftant object, 

 the latter will appear magnified -(Fig. 57.) Let A be 

 a church fleeple, B the eye, C the wire. The rays by 

 which the fleeple would have been otherwife feen are 

 intercepted by the wire, and it is now feen by inflected 

 rays, which make a greater angle than the direct rays, 

 and confequently the fleeple will be magnified. 



In nearly fhutting the eyes, and looking at a candle, 

 there appear rays of light extending from it in vari- 

 ous directions, like comets' tails -, for the light, in paf- 

 iing through the eye-lames, is inflected, and confe*- 

 U 4 * quently 



