And indeed it is the light itself, which after a certain manner, either mixed with shades or other-wise, strikes our eyes and immediately produces that motion in the organ which gives us the color of an object."(6) In examining smooth and rough surfaces to determine the cause of their color, he made use of the microscope, and pointed out the very obvious example of the difference in color of a rough and a polished piece of the same block of stone.

He used some striking illustrations of the effect of light and the position of the eye upon colors.

"Thus the color of plush or velvet will appear various if you stroke part of it one way and part another, the posture of the particular threads in regard to the light, or the eye, being thereby varied.

And 'tis observable that in a field of ripe corn, blown upon by the wind, there will appear waves of a color different from that of the rest of the corn, because the wind, by depressing some of the ears more than others, causes one to reflect more light from the lateral and strawy parts than another."(7) His work upon color, however, as upon light, was entirely overshadowed by the work of his great fellow-countryman Newton.
Boyle's work on electricity was a continuation of Gilbert's, to which he added several new facts.

He added several substances to Gilbert's list of "electrics," experimented on smooth and rough surfaces in exciting of electricity, and made the important discovery that amber retained its attractive virtue after the friction that excited it bad ceased.