"There she is!" yelled Lieutenant McClure, as he stood with his eyes
glued to the periscope glass.

"U-boat driving straight ahead at the smoke curtain. Port the helm!"
he commanded.

The _Dewey_ came around sharp and, in response to the guidance of her
commander, began to ascend.

Having executed a flank movement, the _Dewey_ now was endeavoring to
engineer a surprise attack on the German submarine from the rear. To
all intents, the German commander had not yet noted the approaching
American submersible. He was going after the transports full tilt,
hoping to bore through the destroyers' smoke curtain and torpedo one
of the Yankee fleet.

Quickly the _Dewey_ dived up out of the water, the hatches were thrown
open and the gun crews swarmed on deck, carrying shells for their
guns. Jack and Ted followed Mike Mowrey on deck and dropped into
position behind "Roosey." Gazing ahead they could make out the German
periscope and its foamy trail.

"Fire on that periscope," ordered Lieutenant McClure.

The U-boat was not more than nine hundred yards away, according to the
_Dewey's_ range-finder, and apparently yet unconscious of the proximity
of the American submarine. In a moment the gun was loaded and ready
for firing.

"Bang!" she spoke, and then every eye followed the shot. Commander