Mifcellanea Cufiofa. 109 



prefs the Images of things coloured, as in the for- 

 mer cafe they did the Sun's Image upon a Wall. 

 And by this inequality of Refractions, they be- 

 come not only coloured, but alio very confuted 

 and indiftincl. 



10. Why the Colours of the Hpinbow appear 

 in falling drops of Rain, is alfb from hence evi- 

 dent. For thofe drops, which refract the Rays, 

 difpofed to appear Purple, in greater!: quantity 

 to the Spectators Eye, refract the Rays of othe$ 

 fbrts Co much lefe, as to make them pafs befide 

 it j and fuch are the drops on the infide of the 

 Primary Bow, and. on the outfide of the Secon- 

 dary or Exteriour one. So thofe drops, which re- 

 fract in greateft plenty the Rays, apt to appear 

 red, toward the Spectator's Eye, refract thofe of 

 other forts fo much more, as to make them pafs 

 befide it ; and fuch are the drops on the Exteri- 

 our part of the Primary, and Interiour part of 

 the Secondary Bow. 



1 1 . The odd Phenomena of an infufion of 

 Lignum Nephriticum, Leaf-gold, Fragments of co- 

 lour d Glafs, and fbme other tranfparently colour* 

 ed Bodies, appearing in one Pofuion of one Co- 

 lour, and of another in another, are on thefe 

 grounds .no longer Riddles. For thofe are Sub- 

 ftances apt to reflect one fore of Light, and 

 tranfmit another ; as may be feen in a dark Room s 

 by illuminating them with fimilar or uncompound- 

 ed Light. For then they appear of that Colour 

 ofrily, with which they are illuminated ; but yet 

 in one Pofition more vivid and luminous than in 

 another, accordingly as they are difpofed more or 

 left to reflect or tranfmit the incident Colour. 



1 2. From hence alfb is manifelr the reafbn of 

 an unexpected Experiment, which Mr. Hool(j 

 fomcwhere in his Micrography, relates to have 



made 



