Concerning the 



RAINBOW; 



Which (by a direft Method) is fhewn 

 how to find the Diameter of each 

 Bow, the Proportion of the Refraction 

 being given : Together with the Solu- 

 tion of the Inverfe Problem, or how 

 to fend the Ratio of the Refraction, 

 the Diameter of the Iris being given. 



By Edm. Halle y, F.R.S. 



LL the Writers of Natural Hiftory, 



have particularly defcribed the Rain- 



/ ~~\ bow (a iMeteor fb remarkable for its 

 fair Colours) and given an Account of the 

 Caufes of it. And the Ancient Mythologies, 

 from its wonderful Form and Appearance, 



I N 



thought 



