ed from the papers. The
Blackburns had quarrelled over a contract. Robert had been struck over
the head. He wandered about the isthmus, half-witted, forgetting his
name, nursing one idea. Someone had robbed him, and he wanted his money
back or a different kind of payment, but he couldn't remember who, and he
took it out in angry talk. Then he disappeared, and people said he had
gone to Spain. Of course his wife suspected a good deal. In Blackburn's
desk are pitiful and threatening letters from her which he ignored. Then
she died, and Blackburn thought he was safe. But he took no chances. Some
survivor of those days might turn up and try blackmail. It was safer to
bury himself here."

"Then," Bobby said, "Maria must have brought her father with her when she
came from Spain last summer."

"Brought him or sent for him," Paredes answered. "She's made most of her
money on this side, you know. And she's as loyal and generous as she is
impulsive. Undoubtedly she had the doctors do what they could for her
father, and when she got track of Silas Blackburn through you, Bobby, she
nursed in the warped brain that dominant idea with her own Latin desire
for justice and payment."

"Then," Graham said, "that's what Silas Blackburn was afraid of instead
of Bobby, as he tried to convince us to-night to cover himself."

"One minute, Mr. Paredes," Robinson broke in. "Why did you maintain this
extraordinary secrecy? Nobody would have hurt you if you had put us on
the right track and asked for a little help. Why did you throw sand in
our eyes? Why did you talk all the time about ghosts?"

"I had to go on tiptoe," Paredes smiled. "I suspected there was at least
one spy in the house. So I gave the doctor's ghost talk all the impetus I
could. I was like Howells, as I've told you, in believing the case
couldn't be complete without the discovery of the secret entrance of the
room of death. My belief in the existence of such a thing made me lean
from the first to Silas Blackburn rather than Robert. It's a tradition in
many families to hand such things down to the head of each generation.
Silas Blackburn was the one most likely to know. Such a secret door had
never been mentioned to you, had it, Bobby?"

Bobby shook his head. Paredes turned and smiled at the haggard butler.

"I'm right so far, am I not, Jenkins?"

Jenkins bobbed his head jerkily.

"Then," Paredes went on, "you might answer one or two questions. When did
the first letter