“Yes—­that is all very well,” insisted Kennedy.  “But how about the treasure?”

“Treasure?” repeated Bernardo, looking from one of us to another.

“Yes,” pursued Craig relentlessly, “the treasure.  You are an expert in reading the hieroglyphics.  By your own statement, you and Northrop had been going over the stuff he had sent up.  You know it.”

Bernardo gave a quick glance from Kennedy to me.  Evidently he saw that the secret was out.

“Yes,” he said huskily, in a low tone, “Northrop and I were to follow the directions after we had plotted them out and were to share it together on the next expedition, which I could direct as a Mexican without so much suspicion.  I should still have shared it with his widow if this unfortunate affair had not exposed the secret.”

Bernardo had risen earnestly.

“Kennedy,” he cried, “before God, if you will get back that stone and keep the secret from going further than this room, I will prove what I have said by dividing the Mixtec treasure with Mrs. Northrop and making her one of the richest widows in the country!”

“That is what I wanted to be sure of,” nodded Craig.  “Bernardo, Senora Herreria, of whom your friend wrote to you from Mexico, has been murdered in the same way that Professor Northrop was.  Otaka was sent by her husband to murder Northrop, in order that they might obtain the so-called ‘Pillar of Death’ and the key to the treasure.  Then, when the senora was no doubt under the influence of sake in the pretty little Oriental bower at the curio shop, a quick jab, and Otaka had removed one who shared the secret with them.”

He had turned and faced the pair.

“Sato,” he added, “you played on the patriotism of the senora until you wormed from her the treasure secret.  Evidently rumors of it had spread from Mexican Indians to Japanese visitors.  And then, Otaka, all jealousy over one whom she, no doubt, justly considered a rival, completed your work by sending her forth to die, unknown, on the street.  Walter, ring up First Deputy O’Connor.  The stone is hidden somewhere in the curio shop.  We can find it without Sato’s help.  The quicker such a criminal is lodged safely in jail, the better for humanity.”

Sato was on his feet, advancing cautiously toward Craig.  I knew the dangers, now, of anno-noki, as well as the wonders of jujutsu, and, with a leap, I bounded past Bernardo and between Sato and Kennedy.

How it happened, I don’t know, but, an instant later, I was sprawling.

Before I could recover myself, before even Craig had a chance to pull the hair-trigger of his automatic, Sato had seized the Ainu arrow poison from the table, had bitten the little cylinder in half, and had crammed the other half into the mouth of Otaka.

CHAPTER XIII

THE RADIUM ROBBER

Kennedy simply reached for the telephone and called an ambulance.  But it was purely perfunctory.  Dr. Leslie himself was the only official who could handle Sato’s case now.