( 3^82 ) 
parted from thofe of other kinds, it hath afterwards obftinately 
retained its colour 5 notwithftanding my utmoft endeavours to 
change it. I have refradied it with Prifmes, and refledied it with 
Bodies, which in Day-hght were of other colours 5 I have inter- 
cepted it with the coloured film of Air interceding two compreO 
fed plates of glals 5 tranfmitted it through coloured Mediums,and 
through Mediums irradiated with other forts of Rays, and di- 
verfly terminated itj and yet could never produce any new co- 
lour out of it. It would by contrafting or dilating become more 
brisk, or faint, and by the lofs of many Rays, in fome cafes 
vsry obfcure and dark 5 but I could never fee it changed tit 
fpscie^ 
Yet feeming tranfrautations of Colours may be made , where 
there is any mixture of divers forts of Rays. For in fuch mixtures, 
the component colours appear not, but, by their mutual allaying 
each other, conftitute a midling colour. And therefore, if by 
refraftion, or any other of the aforefaid caafes, the difform Rays, 
latent in fuch a mixture, be feparated, there (hall emerge colours 
different from the colour of the compofition. Which colours 
are not New generated^but only made Apparent by being parted^ 
for if they be again intirely mix'c and blended together, they will 
again compofe that colour, which they did before feparatiom And 
for the fame reafon, Tranfmutations made by the convening of 
divers colours are not real; for when the difform Rays are again 
fevered, they will exhibit the very fame colours, which they did 
before they entered the compofition ; as you fee, Blerv and Tellow 
powders, when finely mixed, appear to the naked eye Green^ and 
yet the Colours of the Component corpufcles are not thereby 
really traafmuted, but only blended* For, when viewed with a 
good Micrc fcope^they (till appear Blm and !D?//winterfperfedly. 
5. There are therefore two forts of Colours* The one original 
andfimple, the other compounded of thefe. The Original or pris 
m3ry colours are^ JR^d, Tellorv, Green, Blew ^^nd z Fielei^purple, 
together with Orange, Indico, and an indefinite variety of Inter- 
mediate gradations. 
6. The fame colours in Specie with thefe Primary ones may be 
al(o produced by compofition : Forj a mixture of Tellorv and Blen> 
m kes Green 5 o( J{ed and Tellow makes Orange i pf Orange 2X\d TeU 
lorofjh green makes j^'Z/on?. And in general, if any two Colours be 
mixed, which inthe feries of thofe, genc^:ated by thePrifmejare 
- • ■ not 
