"We found," said Fleck, his keen eyes fixed on her face as if trying to
read her innermost thoughts, "a British officer's uniform hanging in
Frederic Hoff's closet, proof positive that he is a dangerous spy."

"And," said Carter, pointing to the two clippings lying on Fleck's desk,
"in the old man's waste-paper basket we found those."

Jane picked up the clippings and examined them curiously.

"What are they?" she asked, looking from one to the other; "cipher
messages of some sort?"

"We think so," said Carter. "We don't know yet."

"I've noticed these peculiar advertisements often," said Jane, studying
the clippings, "but I never thought of connecting them with the Hoffs. I
wonder--" Fleck and Carter had their heads together and were talking in
low tones.

"I wonder," said the chief, "what young Hoff is up to. He must have
known the girl was there to spy on him. I can't understand his not
quizzing her."

"He's a cagey bird," Carter replied. "They are both of them expert at
throwing off shadowers. Both of them know, I think, they are
being watched."

"Oh, listen," interrupted Jane, all excitement. "I believe I can read
this cipher. The number of letters in the word in big type at the
beginning of the advertisement is the key. See, this word here is
'remember'--that has eight letters. Read every eighth word in this
advertisement. I've underlined them."

Fleck took the paper quickly from her hand and he and Carter bent
eagerly over it to see if her theory was correct.

REMEMBER

Please, that our new paste, Dento, will
_stop_ decay of your teeth. Sound teeth
are _passports_ to good health and comfort.
No good _business_ man can risk ill health.
It is _closely_ allied with failure. The
teeth if not _watched_ are quickly gone.

USE DENTO

A genuine, safe, pleasing paste for the
teeth, prepared and sold only by the
Auer Dental Company, New York.

"Stop passports business, closely watched," repeated Fleck aloud. "That
certainly makes sense and fits the facts, too. In the last few days we
have drawn the net closely around a gang of supposed Scandinavians who
have been busy supplying passports to suspicious-looking travelers.
Let's see the other advertisement."

Excitedly the three of them read it together as Fleck underscored every
fourth word.

DON'T

Forget it is _imperative_ for one and _all_
to use cleansing _agents_ on teeth th