proaching. Looking out
through a small observation peephole made for this purpose, he saw Mrs.
Baggert hurrying toward the building.

"I wonder what's the matter?" he said aloud, for there was a look of
worriment on the lady's face. Tom threw open the door. "What is it,
Mrs. Baggert?" he called. "Some one up at the house who wants to see
me?"

"No, it's your father!" panted the housekeeper, for she was quite
stout. "He is very ill again, and I can't seem to get Dr. Gladby on
the telephone. Central says he doesn't answer."

"My father worse!" cried Tom in alarm, dropping his tools and hurrying
from the shop. "Where's Eradicate? Send him for the doctor. Perhaps the
wires are broken. If he can't locate Dr. Gladby, get Dr. Kurtz. We must
have some one. Here, Rad! Where are you?" he called, raising his voice.

"Heah I be!" answered the colored man, coming from the direction of the
garden, which he had been weeding.

"Get out your mule, and go for Dr. Gladby. If he isn't home, get Dr.
Kurtz. Hurry, Rad!"

"I's mighty sorry, Massa Tom," answered the colored man, "but I cain't
hurry, nohow."

"Why not?"

"Because Boomerang done gone lame, an' he won't run. I'll go mahse'f,
but I cain't take dat air mule."

"Never mind. I'll go in the Butterfly," decided Tom quickly. "I'll run
up to the house and see how dad is, and while I'm gone, Rad, you get
out the Butterfly. I can make the trip in that. If Dr. Kurtz had a
'phone I could get him, but he lives over on the back road, where there
isn't a line. Hurry, Rad!"

"Yes, sah, Massa Tom, I'll hurry!"

The colored man knew how to get the monoplane in shape for a flight, as
he had often done it.

Tom found his father in no immediate danger, but Mr. Swift had had a
slight recurrence of his heart trouble, and it was thought best to have
a doctor. So Tom started off in his air craft, rising swiftly above the
housetop, and sailed off toward the old-fashioned residence of Dr.
Kurtz, a sturdy, elderly German physician, who sometimes attended Mr.
Swift. Tom decided that as long as Dr. Gladby did not answer his
'phone, he could not be at home, and this, he learned later, was the
case, the physician being in a distant town on a consultation.

"My, this Butterfly seems big and clumsy beside my Humming-Bird," mused
Tom as he slid along through the air, now flying high and now low,
merely for practice. "This machine can go, but wait until I have my new
one in the air! Then I'll sho