to take--less than an
hour!" exclaimed Ned, reproachfully.

"Oh, well, all you wanted to do was to get me out of a rut, as you
called it," laughed Tom. "And you've done it--you and Mr. Peters
together. It jolted up my brain, and I guess I can think better
now. Come on back and watch me tinker away, Ned."

"Not much! I'm going to stay out and get some fresh air while I
can. You'd better, too."

"I will, later."

So Tom turned back to his workshop, and Ned strolled on into the
country, for his day's work at the bank was over. And for some
time after that--until far into the night--Tom Swift worked at the
knotty problem of the photo telephone.

But the young inventor was baffled. Try as he might, he could not
get the image to show on the metal plate, nor could he get any
results by using a regular photographic plate, and developing it
afterward.

"There is something wrong with the transmission of the light waves
over the wire," Tom confessed to his father.

"You'll never do it, Tom," said the aged inventor. "You are only
wasting a whole lot of time."

"Well, as I haven't anything else to do now, it isn't much loss,"
spoke Tom, ruefully. "But I'm going to make this work, Dad!"

"All right, son. It's up to you. Only I tell you it can't be
done."

Tom, himself, was almost ready to admit this, when, a week later,
he seemed to be no nearer a solution of the problem than he was at
first. He had tried everything he could think of, and he had
Eradicate and Koku, the giant, almost distracted, by making them
stay in small telephone booths for hours at a time, while the
young inventor tried to get some reflection of one face or the
other to come over the wire.

Koku finally got so nervous over the matter, that he flatly
refused to "pose" any longer, so Tom was forced to use Eradicate.
As for that elderly man of all work, after many trials, all
unsuccessful, he remarked:

"Massa Tom, I reckon I knows what's wrong."

"Yes, Rad? Well, what is it?"

"Mah face am too black--dat's de trouble. You done want a
white-complected gen'man to stand in dat booth an' look at dat lookin'
glass plate. I'se too black! I suah is!"

"No, that isn't it, Rad," laughed Tom, hopelessly. "If the thing
works at all it will send a black man's face over the wire as well
as a white man's. I guess the truth of it is that you're like
Koku. You're getting tired. I don't know as I blame you. I'm
getting a bit weary myself. I'm going to take a