l. His
face was returning into its iron-like mask. His two hands gripped the
arms of his chair, and he stared at Keith again as if he were looking
through him at something else, and to that something else he seemed to
speak, slowly, weighing and measuring each word before it passed his
lips. "I am not superstitious. It has always been a law with me to have
conviction forced upon me. I do not believe unusual things until
investigation proves them. I am making an exception in the case of Shan
Tung. I have never regarded him as a man, like you and me, but as a
sort of superphysical human machine possessed of a certain
psychological power that is at times almost deadly. Do you begin to
understand me? I believe that he has exerted the whole force of that
influence upon Miriam Kirkstone--and she has surrendered to it. I
believe--and yet I am not positive."

"And you have watched them for six months?"

"No. The suspicion came less than a month ago. No one that I know has
ever had the opportunity of looking into Shan Tung's private life. The
quarters behind his cafe are a mystery. I suppose they can be entered
from the cafe and also from a little stairway at the rear. One
night--very late--I saw Miriam Kirkstone come down that stairway. Twice
in the last month she has visited Shan Tung at a late hour. Twice that
I know of, you understand. And that is not all--quite."

Keith saw the distended veins in McDowell's clenched hands, and he knew
that he was speaking under a tremendous strain.

"I watched the Kirkstone home--personally. Three times in that same
month Shan Tung visited her there. The third time I entered boldly with
a fraud message for the girl. I remained with her for an hour. In that
time I saw nothing and heard nothing of Shan Tung. He was hiding--or
got out as I came in."

Keith was visioning Miriam Kirkstone as he had seen her in the
inspector's office. He recalled vividly the slim, golden beauty of her,
the wonderful gray of her eyes, and the shimmer of her hair as she
stood in the light of the window--and then he saw Shan Tung,
effeminate, with his sly, creeping hands and his narrowed eyes, and the
thing which McDowell had suggested rose up before him a monstrous
impossibility.

"Why don't you demand an explanation of Miss Kirkstone?" he asked.

"I have, and she denies it all absolutely, except that Shan Tung came
to her house once to see her brother. She says that she was never on
the little stairway ba