amount of light it received.

"There, I guess we're all ready, Ned," announced Tom, at last.
"Now you go to your little coop, and I'll shut myself up in mine.
We can talk over the telephone."

Seated in the little booth in one of the smaller of Tom's shops,
Ned proceeded with his part in the new experiment. A small shelf
had been fitted up in the booth, or closet, and on this was the
apparatus, consisting of a portable telephone set, and a small
box, in which was set a selenium plate. This plate had been wet by
a spray of water in order to test Tom's new theory.

In a similar booth, several hundred feet away, and in another
building, Tom took his place. The two booths were connected by
wires, and in each one was an electric light.

"All ready, Ned?" asked Tom, through the telephone.

"All ready," came the answer.

"Now then, turn on your switch--the one I showed you--and look
right at the sensitized plate. Then turn out your light, and
slowly turn it on. It's a new kind, and the light comes up
gradually, like gas or an oil lamp. Turn it on easily."

"I get you, Tom."

Ned did as requested. Slowly the illumination in the booth
increased.