Mr. Fleck."

"Indeed," she replied, "what is it?"

"She wants you to go down-town at once and meet her at Room 708--you
know the building."

"Aren't you coming, too?"

"Not right away. I have some errands to do in the neighborhood. I've got
to buy a book for a birthday present. There's a library around here
somewhere, isn't there?"

"Just across the street," said Jane, entering into the spirit of the
masked conversation with interest. "I was looking at a fine book over
there a few minutes ago. You'll find it on the second shelf--the fifth
book from the end, on the north side of the store."

"I'll remember that," said Carter, repeating, "the fifth book on the
second shelf."

"That's right," said Jane, as they left the drug-store together.

"Which way did the old man go?" asked Carter.

"Down Broadway--toward home," she replied. "I wanted to follow him, but
it seemed more important to stay here and watch to see if any one came
for the message he left there in the book."

"You did just right, and the Chief is tickled to death. He wants to see
you right away. You have a copy of the message, haven't you?"

"Yes, do you wish to see it?"

"No, but he does. Has anybody entered the store since you were there?"

"Nobody, that is no one but a couple of girls."

"What did they look like? Describe them."

"Why," Jane faltered, "I did not really notice. I was not looking for
girls. I was watching to see that no other men entered the store."

Carter shook his head.

"You ought to have spotted them, too. You never can tell who the Germans
will employ. They have women spies, too,--clever ones."

"I never thought of their using girls," protested Jane.

"Humph," snapped Carter, "ain't we using you? Ain't one of our best
little operatives right this minute working in a nursegirl's garb
pulling a baby carriage with a baby in it up and down Riverside Drive?
Well, it can't be helped. You'd better beat it down-town to the Chief
right away."

"I'll take a subway express," said Jane, feeling somewhat crestfallen
at his implied suggestion of failure.

Twenty-five minutes later found her once more in Mr. Fleck's office.
Thrilling with the excitement of it all she told him in detail how she
had followed old Hoff and of his peculiar actions in the bookstore.

"And here," she said, presenting the postcard, "is an exact copy of the
cipher message he left there. I copied every figure, in the columns,
just as they were set do