"Massa Chadwick send me on de bustelbolorium," explained Jupe, who had
a vocabulary that was all his own, "for yo' alls to come right away by
his laburnumtory."

"All right, Jupe, we'll be right over," said Jack, "just as soon as
we've got some of this grease off our hands."

The boys' workshop was equipped with a washbasin and they soon made
themselves presentable. Then they hurried to Mr. Chadwick's workshop.
They found him standing before a roughly-built table on which were
ranged some odd-looking bits of apparatus.

There was a gasoline motor in one corner, geared to a generator--or
what appeared to be one--from which feed wires led to a square metal
box on the table. Attached to this metal box was a sort of horn-shaped
mouthpiece something like the transmitter of a telephone. Hanging from
its side was what looked like an enlarged telephone receiver. Jack
regarded his father questioningly.

"You sent for us, dad?"

"Yes, Jack," was the reply. "I'm in a quandary. Have you any idea what
this apparatus is?"

Both boys shook their heads.

"Looks like some kind of a telephone," ventured Tom.

"It is a telephone," replied Mr. Chadwick.