This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1673 edition. Excerpt: .4. Whiteness in all respects like that of the Sun's immediate light and of all the usual objects of our senses cannot be compounded of two simple colors alone.

For such a composition must be made by rays that have only two degrees of refraogibility, by Des. 1. and 3 3 and therefore it cannot be like that of the Sunslight, by Prop. 1; Nor, for the fame reason, like that of ordinary white objects. 5, Whiteness $ Whiteness in all respects like that of the Sun's immediate light cannot be compounded of simple colors without an indefinite variety of them For to such a composition there are requisite rays indued with all the indefinite degrees of re frangibility, by Prop. i. And those infer as many simple colors, by Des. i.

and 3. and Prop, 2. and 3. To make these a little plainer, I have added also the Propositions that follow. 6. The rays of light do not act on one another in passing through the fame Medium. This appears by several passages in theTransaSiotti 5097, 5098, rioo, andsioi. and is capable of further proof.

7. The rays of light suffer not any change of their qualities from refraction. 8- Nor afterwards from the adjacent quiet Medium These two Propositions are manifest de facto in homogeneal light, whose color and refrangibility is not at all changeable either by refraction pr by ihe contermioation of a quiet Medium And as for heterogeneal light, it is but art aggregate of several forts of homogeneal light, no one fort of which suffers auy more alteration than if it were alone, because the rays act not on one another, by Prop. 6. And therefore the aggregate can suffer none. These two Propositions also might be further proved apart by Experiments, too long to be here described 9. There can no homogeneal colors be educed out of ligh.