books that tramp has hidden--there are marvels, miracles! But this

was not a method, it was an idea, that might lead to a method by

which it would be possible, without changing any other property of

matter--except, in some instances colours--to lower the refractive

index of a substance, solid or liquid, to that of air--so far as all

practical purposes are concerned."

"Phew!" said Kemp. "That's odd! But still I don't see quite ... I

can understand that thereby you could spoil a valuable stone, but

personal invisibility is a far cry."

Precisely," said Griffin. "But consider, visibility depends on the

action of the visible bodies on light. Either a body absorbs light,

or it reflects or refracts it, or does all these things. If it

neither reflects nor refracts nor absorbs light, it cannot of

itself be visible. You see an opaque red box, for instance, because

the colour absorbs some of the light and reflects the rest, all the

red part of the light, to you. If it did not absorb any particular

part of the light, but reflected it all, then it would be a shining

white box. Silver! A diamond box would neither absorb much of the

light nor reflect much from the general surface, but just here

and there where the surfaces were favourable the light would

be reflected and refracted, so that you would get a brilliant

appearance of flashing reflections and translucencies--a sort of

skeleton of light. A glass box would not be so brilliant, not so

clearly visible, as a diamond box, because there would be less

145

The Invisible Man