“The most surprising and wonderful
Composition was that of Whiteness…
There is no one sort of Rays which alone
Can exhibit this. Tis ever compounded
And to its composition all the aforesaid
 Primary colours, mixed in due proportion.
I have often in admiration beheld
That all the colours of the prism being
 Made to converge and thereby to be
Again mixed as they were in the light before
It was incident upon the prism…
Entirely and perfectly white”