going on. That man
out there is a spy!"

CHAPTER III

UNEXPECTED ACTION

If red-headed, freckle-faced Jerry Macklin, star sprinter of Brighton,
ever ran in his life he ran that night. Down across the uneven,
hill-dotted dumps he tore at a speed that would have put his school
records to shame. Three times he fell, but each time on the instant he
was up and off again, without even a thought as to whether or not he had
injured himself.

And all the time he kept repeating in his mind, "There's a spy out there
planning dangerous things for the navy yard and the United States. Joe's
in the icy water watching him, and I must get help as fast as I can."

It was good, too, that he did put forth the last ounce of his strength.
Sergeant Martin was just passing through the navy yard gate as Jerry
arrived, his uniform covered with loose ashes and dirt, and his hands
bleeding from stone cuts received in his falls.

To Sergeant Martin, between gasps, Jerry managed to blurt out enough to
make the other understand. Within two more minutes Sergeant Martin had
imparted the vital information to the captain of the company of marines
charged with guarding the navy yard for that particular night. The
captain sent two aides scurrying, one to his major, the other to the
office of the navy yard commandant.

Twenty marines, fully armed, were hurried aboard a launch that
constantly was kept under steam for just such an emergency, and, with
Jerry directing, the boat swung out to Joe's aid.

Rapidly as Jerry had traveled the distance between the spot where Slim
waited and the navy yard itself, it seemed like ages to Joe, out there
in the icy water, a quarter of a mile from shore.

At first the tense excitement of the manhunt had made him unmindful of
the low temperature, and he swam with strong, even, silent strokes that
sent his lithe body gliding through the current noiselessly; but when he
had come within forty feet of the rowboat its lone occupant had turned
suddenly, as though scenting danger, and Joe, after waiting for a few
seconds to see what might happen, considered the absolute silence an
omen of danger and had dived under water, staying there as long as he
could, and coming to the surface at an entirely different point from the
boat.

After that the cold got to the very heart of him. His muscles grew numb,
he felt his strength waning, and he had to bring the whole force of his
will to bear to keep from turning back to