ed on the faces of
the three lads. Then he chuckled in a singular way and said:

"Wait till I get through, young man. I do not take you for a fool
ordinarily, but you can easily make a fool of yourself over this
matter."

He had taken the short white hair, which was very coarse, in his
fingers, having separated it from the others.

"Notice the peculiar place where this hair seems to grow," he directed.
"It is not a part of the fetlock, but the fetlock hid it from view. I am
going to pull this hair out, but first I want you to notice that there
is another hair, it seems, on the other side of the ankle, and it is
just like this. See it?"

The boys saw it.

"In a moment you won't see it," declared the doctor, as he adjusted the
tweezers, getting a careful grip on the end of the hair. "Here it
comes."

Then he quickly drew it out and Nemo started a bit, but was quieted by
Grody.

"Young man," said the doctor, "look at this. This hair appeared to be
about an inch in length, but now it is three inches long. It is not
broken off, and yet it has no root. I will guarantee there is not
another hair on this horse like it! I will guarantee it did not grow on
this horse! I will guarantee it was what made this horse lame! And I do
not want my fee if this horse shows any lameness two hours from now!"

The boys were astonished, as their faces indicated.

"But, doctor, I do not understand!" cried Frank. "You must explain. How
could a hair----"

"I will explain. It's an old trick, but one seldom tried. This hair came
from the tail of a white horse. It was threaded into a long, keen
needle. The fellow who got at your horse yesterday was an expert. With
one jab of that needle he passed the hair through the flesh just back of
this cord. It went in at one side, and came out on the other. After
that, while he was pretending to look at the horse's feet, he clipped
off the ends, and the hair was left in there. It could remain a day or
so without doing any particular injury, but it was bound to make the
horse lame as soon as he used that leg much. If it had been left there
permanently it might have ruined the horse. That is all, young man."

"Why was a white hair chosen, doctor?"

"The fellow felt sure it would not be noticed, and yet he could quickly
locate it by its color when the time came for him to cure your horse of
its lameness."

Once more the boys looked at each other, and this time it was plain they
realized there wer