g i Mifcellanea Curiofa. 



Fourth Iris , the Sine of Incidence will be 



V?£_ HZ an d t he Sine of the Refracted 



24 24^ 



Anele ^ 2.111 — i- : and in like manner of 



D 24JT 24 



the reft. Farther, 'twill be found by Calcu- 

 lation, that (taking Carte?* Proportion) the 

 Primary Iris is diftant 41 °. 30'. from the 

 Point oppofite to the Sun ', the Secondary , 

 5 1 0 . 5 5'. from the fame. The Third, 40 0 . 20'. 

 and the Fourth, 45 °. 33'. from the Sun it felf , 

 which Iris's perhaps were hardly ever feen for 

 the reafons before mentioned. 



And thus much may fuffice concerning the 

 Magnitude of the hides ^ in the perfpicuous 

 Drops of a Fluid, whofe Refra&ive Power is 

 known. It remains that nothing be faid con- 

 cerning the Colours, which this Phenomenon 

 prefents, with the orders of them in each 

 fort of Iris, according to all the poflible Vari- 

 ations of the Refra&ion. 



And here we muft know eipechlly, that 

 the Acute and Sagacious Mr. Newton, has 

 found by molt clear Experiments, that the 

 Rays of Light are not Simple and Vniform, as 

 they iffue out of the Luminous Body, but the pure 

 white Light which we fee, conjtjfs of Corpufcles of 

 all kinds of Colours, mix'd and hurried with 

 a violent Motion, one amongft another. And 

 that the diverfity of the Colours of things 

 arifes, according to the various Dilpolitions 

 thofe Obje&s have, to Refract or Refleft this 

 or that peculiar kind of Light. 



The Proof of which is manifeft from Refra- 



ftions, 



