here she had thrown it, and examined it
carefully for the first time.

It had not been originally intended as a jewel-case, that was clear; and
as Maxine's voice had rung unmistakably true when she denied all
previous knowledge of it to the police, I judged that the diamonds had
not been in it when the Duchess entrusted them to du Laurier. He would
almost certainly have described to Maxine the box or case which had been
stolen from him, and if the thing pulled out from the sofa-hiding-place
had recalled his description, she must have betrayed some emotion under
the keen eyes of the Commissary of Police.

The case which, it seemed, I had brought to Paris, looked as if it might
have been made to hold a peculiar kind of cigar, much longer than the
ordinary sort. Within, on either side, was a partition, and there was a
silver clasp on which the hallmark was English.

"English silver!" I said to myself, thoughtfully. The three men who had
travelled in the carriage with me from London to Dover were all English.
Of the trio, only the nervous little fellow who had reserved the
compartment for himself had found the smallest possible opportunity to
steal the treaty from me, and exchange for it this red leather case
containing a diamond necklace worth twenty thousand pounds. If he
possessed the skill and quick deftness of a conjurer or a marvellously
clever professional pickpocket, as well as the incentive of a paid spy,
he might conceivably have done the trick at the moment of alarm on the
boat's gangway, not afterwards; for when he had pressed near me in the
Gare du Nord he had been on the wrong side. But for my life I could not
guess the motive for such an exchange.

Supposing him a spy, employed to track and rob me of what I carried, why
should he have made me a present of these rare and precious diamonds?
Would the bribe for which he used his skill reach anything like the sum
he could obtain by selling the stones? I was almost sure it would not;
and therefore, having the diamonds, it would have been far more to his
advantage to keep them than to stuff them into my pocket, simply to fill
up the space where the case with the treaty had lain. There would not
have been time yet for the real diamonds to have been copied in
Amsterdam, therefore it would be useless to build up a theory that the
stones given me might be false.

Besides, I reminded myself, if the man were a spy whose business was to
watch and be near me, why hadn