ery reason to believe he is an Englishman. He
was pro-German, as he would have been pro-Boer. What he seeks to attain
we do not know--probably supreme power for himself, of a kind unique in
history. We have no clue as to his real personality. It is reported that
even his own followers are ignorant of it. Where we have come across his
tracks, he has always played a secondary part. Somebody else assumes
the chief role. But afterwards we always find that there has been some
nonentity, a servant or a clerk, who has remained in the background
unnoticed, and that the elusive Mr. Brown has escaped us once more."

"Oh!" Tuppence jumped. "I wonder----"

"Yes?"

"I remember in Mr. Whittington's office. The clerk--he called him Brown.
You don't think----"

Carter nodded thoughtfully.

"Very likely. A curious point is that the name is usually mentioned. An
idiosyncrasy of genius. Can you describe him at all?"

"I really didn't notice. He was quite ordinary--just like anyone else."

Mr. Carter sighed in his tired manner.

"That is the invariable description of Mr. Brown! Brought a telephone
message to the man Whittington, did he? Notice a telephone in the outer
office?"

Tuppence thought.

"No, I don't think I did."

"Exactly. That 'message' was Mr. Brown's way of giving an order to his
subordinate. He overheard the whole conversation of course. Was it after
that that Whittington handed you over the money, and told you to come
the following day?"

Tuppence nodded.

"Yes, undoubtedly the hand of Mr. Brown!" Mr. Carter paused. "Well,
there it is, you see what you are pitting yourselves against? Possibly
the finest criminal brain of the age. I don't quite like it, you know.
You're such young things, both of you. I shouldn't like anything to
happen to you."

"It won't," Tuppence assured him positively.

"I'll look after her, sir," said Tommy.

"And I'll look after YOU," retorted Tuppence, resenting the manly
assertion.

"Well, then, look after each other," said Mr. Carter, smiling. "Now
let's get back to business. There's something mysterious about this
draft treaty that we haven't fathomed yet. We've been threatened with
it--in plain and unmistakable terms. The Revolutionary element as good
as declare that it's in their hands, and that they intend to produce it
at a given moment. On the other hand, they are clearly at fault about
many of its provisions. The Government consider it as mere bluff
on their part, and