"Brockley died while he was there," continued Harry, in a reminiscent tone. "His death was a sudden one. He was murdered. It was a shock to you."
"It was a shock," admitted Powell.
"Before he died, Brockley gave you something. What, I do not know. I presume, however, that it involved information of a certain sort. It may have explained, to some degree, why Brockley died.
"Of course, the cause of his death has been traced to Parisian criminals — Apaches. But you know something which underlies it all."
"Where did you get that idea?" asked Powell, with a hollow laugh.
"My source of information is my secret," replied Harry, "just as your fund of information is your secret. Perhaps a fair exchange would be to our mutual liking."
"Not to mine," declared Powell. "What I know, I keep to myself. What I have learned" -
he caught himself — "what I may have learned was given to me in confidence. That's enough, isn't it?"
"Yes," said Harry calmly. "But sometimes, people learn too much. Herbert Brockley did.
He passed the information on to you."