“Excuse me,” said Kerry, “but didn’t I see you somewhere last night?”

“Yes,” she said.  “I was sitting just inside the door at—­”

“Right!  I remember,” interrupted Kerry.  He continued to stare.  “Before you say any more, miss, I have to remind you that I am a police officer, and that you may be called upon to swear to the truth of any information you may give me.”

“Oh, of course!  I know.”

“You know?  Very well, then; we can get on.  Who gave you my address?”

At the question, so abruptly asked, Mollie felt herself blushing again.  It was delightful to know that she could still blush.  “Oh—­ I . . . that is, I asked Scotland Yard "

She bestowed a swift, half-veiled glance at her interrogator, but he offered her no help, and: 

“They wouldn’t tell me,” she continued.  “So—­I had to find out.  You see, I heard you were trying to get information which I thought perhaps I could give.”

“So you went to the trouble to find my private address rather than to the nearest police station,” said Kerry.  “Might I ask you from whom you heard that I wanted this information?”

“Well—­it’s in the papers, isn’t it?”

“It is certainly.  But it occurred to me that someone. . . connected might have told you as well.”

“Actually, someone did:  Miss Margaret Halley.”

“Good!” rapped Kerry.  “Now we’re coming to it.  She told you to come to me?”

“Oh, no!” cried Mollie—­“she didn’t.  She told me to tell her so that she could tell the Home office.”

“Eh?” said Kerry, “eh?” He bent forward, staring fiercely.  “Please tell me exactly what Miss Halley wanted to know.”

The intensity of his gaze Mollie found very perturbing, but: 

“She wanted me to tell her where Mrs. Sin lived,” she replied.

Kerry experienced a quickening of the pulse.  In the failure of the C.I.D. to trace the abode of the notorious Mrs. Sin he had suspected double-dealing.  He counted it unbelievable that a figure so conspicuous in certain circles could evade official quest even for forty-eight hours.  K Division’s explanation, too, that there were no less than eighty Chinamen resident in and about Limehouse whose names either began or ended with Sin, he looked upon as a paltry evasion.  That very morning he had awakened from a species of nightmare wherein 719 had affected the arrest of Kazmah and Mrs. Sin and had rescued Mrs. Irvin from the clutches of the former.  Now—­here was hope. 719 would seem to be as hopelessly in the dark as everybody else.

“You refused?” he rapped.

“Of course I did, Inspector,” said Mollie, with a timid, tender glance.  “I thought you were the proper person to tell.”

“Then you know?” asked Kerry, unable to conceal his eagerness.

“Yes,” sighed Mollie.  “Unfortunately—­I know.  Oh Inspector, how can I explain it to you?”

“Don’t trouble, miss.  Just give me the address and I’ll ask no questions!”