"Two Green Eyes Glowed at Him Out of the Darkness—Then Blinked Shut"

"Black Light."
By Ralph Milne Farley (Roger Sherman Hoar, 1887-1963).
First appearance: Astounding Stories, August 1936.
Short short short story (4 pages).
Online at SFFAudio (HERE) (PDF).

"The dull thud of a falling body. Then silence."

How do you protect someone when the would-be killer can't be seen? With "pigments which, although invisible to unassisted eyesight, nevertheless produce all the different colors of the octave above human vision; also the octave below. . . . Simple, isn't it?"

Resources:
- The technology employed in our story, relatively new at the time, is discussed in a Wikipedia article (HERE).
- Ralph Milne Farley was the very definition of the early science fiction pulp writer, but
at crime fiction he wasn't anything to write home about; for more go (HERE), (HERE),
and (HERE).
- We've communed with Farley a couple of times already: "Who Killed Gilbert Foster?" (HERE) and "The Time-Traveler" (HERE).