facie
evidence that Frederic Hoff was a spy. What puzzled Carter most was how
Hoff managed to smuggle the uniform in and out of the apartment without
being observed. For more than two weeks now every parcel that had
arrived at the house of the Hoffs had been searched before it was
delivered. The house had been constantly under the strictest
surveillance. It was out of the question for him to have worn the
uniform in or out as it could not be easily concealed under
other clothing.

"There's somebody else in this place in league with the Hoffs," he
muttered to himself. "I wonder who it can be."

He looked at his watch. The old servant had been out now nearly half an
hour. She was likely to return at any moment. He must work quickly.
Swiftly he went through the dresser drawers but without satisfactory
result. There was no time for him to do more. He hastened into the
living room and summoned his aides.

"Find anything, Bob?" he asked.

"Not a thing."

"Beat it up to the roof," he directed. "Have you those field glasses
with you?"

"Sure," replied the operative, "and the handkerchiefs, too."

"All right. Get up there before she starts down. Begin putting up
handkerchiefs and appear to be watching the river. That will mix her up
so she will not know what to do. She will not dare to leave the roof
while you are there. When we're through I'll send the elevator man up
for you with the message that we have found the short circuit."

He turned to the other operative.

"Find anything, Williams?"

"Only this."

Carter's face brightened as his assistant held out to him two copies of
an afternoon newspaper. In each of them a square was missing where
something had been cut out.

"I found them in the waste-paper basket by the old man's desk," the man
explained, "and there was some ashes there--ashes of paper--as if he had
burned up something. Maybe it was what he cut out of those papers. I
could not tell."

"We've got to get copies of those papers at once and see what it was.
Come on, I'm going to take them to the Chief. We can get the papers on
the way down."

Calling the other operative from the roof, before he even had had time
to attract the attention of Lena Kraus by his activities, they hastened
back to the office, where Fleck and Carter together scanned the two
papers from which the clippings had been taken.

"Why," said Carter disappointedly, "it is just a couple of
advertisements he cut out--advertisement