As they left the dining-room they heard an unexpected noise at
one of the windows. They looked quickly up, and Jack saw the
face of a man staring in.

Before he could cry out, there came the sound of Washington's
voice:

"Hey dar! Git away from dere! Skedaddle, now, or I'll
prognostigate yo' inter modicums ob transmigatory infatisamatisms!"

The face disappeared from the window, and the sound of footsteps
in rapid retreat was heard.





CHAPTER VI

BUILDING THE PROJECTILE


"Did you see that?" exclaimed Jack.

"What?" asked Professor Henderson quickly.

"Some one at the window," replied Jack.

"I saw the face," added Mark. "It was a man looking in."