"The other two do not matter," he said, looking her full in the eyes again. "But the third is ---- yourself."
Mercia flushed a sudden scarlet eyes which a moment before had been alight with pent-up anxiety and repressed emotion blazed in an instant into hot indignation.
"Arrest me?" she cried. "What do you mean? How dare you suggest such a thing?"
Delbury made a gesture of restraint.
"For your own good, madam, I must ask you not to get excited," he said. " this is a very grave matter and one which is as distasteful to me as it must be to you. I ask you to believe that, in all fairness to me. I will not detain you any longer than I can possibly help. As soon as I have obtained from you such information as I require I will answer as many questions of yours as you wish. also your mother can be present when I tell you."
Mercia subsided; she sat down and folded her hands in her lap, but she regarded the detective with an air of aggressive enmity which still retained a touch of proud defiance.
Delbury noted the signs and against his will, Mercia went up another notch in his estimation . The girl was either another Duse, immaculate in her command of every emotional phase, or she was as innocent as the air she breathed.
He cleared his throat and took the situation into both his firm, capable hands. He wasn't the man to let a situation get out of hand, much less let a woman take the lead in an examination.
"Mr. williard lyall is your father, I believe?" he asked, slipping a notepad on to his knee.
"Yes."
"What is his business?"
" He has an office in the city; he is connected in some way with the stock exchange."
"Yes, I know, but--- That is a little vague, is it not?"
"That is all I can tell you about his business affairs. He never discusses business matters at home."
" But surely, miss Lyall, as his daughter, having lived several years with him at an age when a girl knows a good deal about the world and ways of her parents, you---"
Mercia interrupted him deliberately:
"All I know is that his business concerns stocks and shares. You can easily discover All you require to know by making a few inquiries at his office. Dad has been established in business there since soon after I was born. perhaps mother could tell you more about it."
"What time did he leave home last night?"
"I haven't the faintest idea. Neither has anyone else in the house. I have already questioned all the servants. nobody knew he was going out; nobody knew he was gone. He went to bed fairly Last night; and it seems that he went out after the house had been locked up for the night, After the servants had retired."
"What did he go out for?"
"I really don't know. it is as puzzling to me as it is, apparently to you."
"Has he ever done such a thing before?"
"Never. At least, not to my knowledge. He may have done, of course and returned equally secretly; in which case nobody in the house would be any the wiser."
"Pricisely." The detective made a few rapid notes.
"Now as to his object," he said. "Do you know where he went? By that I mean, when he left this house in the dead of the night, do you know whom he intended visiting?"
"No," said Mercia dryly.
"Is that the truth, miss Lyall?"
Mercia flushed. "I am answering your questions as truthfully as I can," she said, and there was a little chilliness In her voice and in her face. "Please remember that you are keeping me in the dark about something that vitally concerns my father, and therefore concerns me. also that you are a police man, and that it is not one of my usual customs to submit to cross-examination by representatives of the law."
Delbury bowed.
"You know a Mr. Valmon Dain, I think," he said, switching the line of inquiry.
"Yes I know Mr. Dain very well."
"He is a great----er-- friend of yours?"
"Certainly."
"I hope you won't think me impertinent or rude, miss Lyall, but the common talk in the neighborhood, both here and at Hendon, is that you and Mr. Dain were practically engaged. is that so?"
Mercia shook her head, "No, I don't think that is quite true," she said, with a diffident little smile. ", Rather a difficult matter to discuss, isn't it? Surely it isn't vitally interesting to you, is it?"
"I'm sorry, madam--- but it happens to be as important to you as it is to me. Would you mind being a little more explicit. Gossip is not generally far wrong in these intimate matters. And it is fairly common knowledge that you and Mr. Dain were being seen about a good deal together."
"Oh yes. That is perfectly true. I think he would admit that himself."
"Theatres, dances, balls, reception and such like?"
"Yes. he has told me that he prefers my company for such little pleasures in preference to that of any of his feminine friends."
"That means, bluntly, that he would rather be with you than anyone else during his free hours."
Mercia nodded. "Yes, I rather think so," she said.
"And you with him?"
"Yes," Mercia was quite frank about that. Her reply and the way she made it seemed to say: "What's the use of being silly about a thing like that? it's the truth, so why not say so and have done with it?"
A glow of satisfaction came into Delbury's eyes , and his next question came with something about it of the air of the hunter out on a hot scent.
"And did your father approve of this companionship?"
"Oh yes. He sincerely hoped that something more would come if it."
Delbury nearly gasped. He looked flabbergasted. He was prepared to have staked his life that Mercia would have admitted a fierce parental objection to his obvious approaching engagement. Her calm statement knocked the ground from under his feet. it demolished, with one simple stroke his whole theory of motive. And he was equally prepared to swear that Mercia was telling the truth.
"H'm," he said perplexedly. "And your mother, was she as satisfied about it as your father?"
"Why , of course. But you know you are know you are taking a good deal for granted, Mr. Delbury a good deal more than I think you have a right to. Mr. Dain and I have only known each other a very short time--- four months, or five months at most."
Delbury looked at her and chewed the end of his pencil.
"would it surprise you to know that your father went out to see Mr. Dain last night?" he asked.
"No---- I don't think it would surprise me very much-- not now."