"Would it have been possible, think you, for it to have been tampered
with while at the city hall?"

"Quite impossible, I should say. There were guards at the entrance to
the room itself, and sentries were posted at the great doors below. In
fact, I would be prepared to swear that no one entered the room save
myself and my brother's faithful friend."

"Your brother's friend?" von Marquart repeated suspiciously. "Who is he?
Perhaps he can throw some light upon the affair."

This point had never struck me, and I thereupon told Strekwitz to summon
Bertram to my presence without delay. He did so, and a few minutes
later, the man we wanted entered the room. Strekwitz had told him
nothing, so that he was quite unprepared for the news I had to give him.
On hearing it his grief was as great, and plainly as sincere, as my own
had been.

"I can scarcely believe it," he said, after he had heard what we had to
tell. "What possible motive can anyone have had for such a dastardly
deed?"

I could furnish him with no answer that would be in any way
satisfactory. Strekwitz inclined to the belief that it was the work of
the enemy--an act of revenge, in fact, for the defeat they had suffered
at our hands. Von Marquart, however, ridiculed the notion.

"No," he said, "there is more behind it than meets the eye. We must look
elsewhere for a solution of the mystery."

Suddenly Bertram uttered an exclamation.

"Why on earth didn't I think of it sooner?" he cried. "If I'm not
mistaken, I can explain everything."

"What do you mean?" I asked impatiently. "What do you remember? Tell us
quickly."

"The man I ran into, in the street at Zaarfburg," he replied.
"Rodriguez, who was with us in South America. Was it possible that his
appearance in the city was only a coincidence, or had he some more
sinister object in view? He was aware of the mysterious marks upon your
brother's body, and knew they were connected with the hidden diamonds.
Seeing that he was dead, and that he might never have another
opportunity, is it not quite possible that he would be anxious to
penetrate the secret before it was too late?"

All this was so much Greek to von Marquart and Strekwitz. They knew
nothing, it must be remembered, of Max's past life, consequently they
had not heard of Moreas, or of the now famous expedition in search of
the diamonds. In a few words I enlightened them, and then we fell to
considering the problem that Bertram had set before us. H