1 1 6 Mifcellanea Curiofa. 



mud be made by Rays that have only two De- 

 grees of Refrangibility, by Def. i and J. and 

 therefore it cannot be like that of the Sun's Light. 

 by Prop. i. nor, for the lame Reafbn, like that 

 of ordinary" white Objects. 



5. Whitenefs, in all refpe&s, like that of the 

 Sun's immediate Light, cannot be compounded 

 of Simple Colours without an indefinite Variety 

 of them. For to fuch a Compofition, there are 



, requifite Rays endu'd with all the indefinite De- 

 grees of Refrangibility, by Prop. 1. And thofe 

 infer as many Simple Colours, by Def. 1 and 3. 

 and Prop. 1 and 3. 



To make thefe a little plainer, I have added 

 alfo the Proportions that follow. 



6. The Rays of Light do not a£fc on one ano- 

 ther, in paffing through the fame Medium. 



7. The Rays of Light differ not any change 

 cf their Qualities from Refraction. 



8. Nor afterwards from the adjacent quiet 

 Medium : Thefe two Proportions are manifeft de 

 Fafto in Homogeneal Light, whofe Colour and 

 Refrangibility is not at all changeable, either by 

 Refraction, or by the Contermination of a quiet 

 Medium. And as for Heterogeneal Light, it is 

 but an Aggregate of feveral forts of Homogeneal 

 Light, no one fort of which fuffers any more 

 alteration than if it were alone ; becaufe the Rays 

 -act not on one another, by Prop. 6. and there* 

 fore the Aggregate can fuffer none. Thefe two 

 Propofitions alio might be further proved apart, 

 by Experiments too long to be here defcribed. 



9. There can no Homogeneal Colours be re* 

 duced out of Light by Refraction, which were 

 not commixt in it before ; Becaufe by Prop, 7. 

 and 8. Refraction changeth not the Qualities of 

 the Rays, but only leparates thofe which have 



divers 



