"No, no, I can't explain because I don't understand myself. But
Ah Fu goes to a place in Shadwell regularly and buys young birds,
always very young ones and very little ones."

"For what or for whom?"

"I don't know."

"Have you an aviary in your house?"

"No."

"Do you mean that they disappear, these purchases of Ah Fu's?"

"I often see him carrying a cage of young birds, but we have no
birds in the house."

"How perfectly extraordinary!" muttered Durham.

"I distrust Ah Fu," whispered the girl. "I am glad he did not
see me with you."

"Young birds," murmured Durham absently. "What kind of young
birds? Any particular breed?"

"No; canaries, linnets--all sorts. Isn't it funny?" The girl
laughed in a childish way. "And now I think Ah Fu will have gone
in, so I must say good night."

But when presently Detective Durham found himself walking back