Whom the Gods Love by Kate Ross

Sons, in the Strand. It's a hardware showroom—grates and lamps and such. Hard by it, there's a passage, very narrow, couldn't have fit the carriage through. Don't know where it leads.
    "Mr. and Mrs. Falkland was just coming out of the showroom when a young 'oman, looked like a servant, come out of the passage. When she seed the master and mistress, she stopped short, then she ran up and spoke to 'em. Next thing, she and the mistress hurried off through the passage, and the master come back and told Luke and me that a woman friend of the mistress's was took sick, and the mistress had gone to see her. Said she'd send for the carriage again if she needed it. And we went home, and that's how and about it."
    "What do you know about this friend?"
    "Naught, sir. 'Cept that the girl was her servant. She come up to Mrs. Falkland 'coz she recognized her in the street." 
    "That seems a singular coincidence," Julian remarked.
    Joe shrugged.
    "Don't you think so?" Julian turned to Luke.
    "I don't know anything about it, sir," Luke said shortly. 
    Julian regarded him politely, as if expecting him to say more. It was a tactic that often provoked people into nervous speech, but this time it failed. Luke shifted about in his seat, avoiding Julian's eyes, but said nothing.
    "Did Mrs. Falkland send for the carriage to bring her home?" Julian asked Joe.
    "No, sir."
    "Then how did she get home?"
    Luke spoke up unwillingly. "She came in a hackney coach, sir."
    "How do you know?"
    "I let her in, sir."
    "When was that?"
    "About an hour before dinner, sir."
    "Which would make it—?"
    "About six, sir."
    "How long had she been gone?"
    "Three hours, sir."
    "You were keeping track of the time?"
    Luke coloured. "No, sir."
    "Then how do you know so precisely?"
    "I don't know precisely, sir. It was three hours more or less."
    "Why are you so reluctant to talk about this incident?" 
    Luke said, very clearly and carefully, "I beg your pardon, sir. I'm not reluctant to talk about it. It's just that there's nothing to say. Mrs. Falkland's friend was took ill, so she went to see her. She came home a few hours later, and I let her in."
    "Didn't it strike you as curious that Mrs. Falkland should have a friend in that neighbourhood?"
    "It's not my place to be curious, sir."
    "Did she say anything to you about her friend when she returned?"
    "No, sir."
    "What frame of mind was she in?"
    "I—I couldn't say, sir."
    "Was she distressed about her friend?"
    "She wouldn't talk to me about it if she was!"
    "See here," cut in Nichols, "that's no way to speak to a gentleman. Beg Mr. Kestrel's pardon at once."
    "Yes, sir. I beg your pardon, Mr. Kestrel."
    Julian inwardly wished Nichols at the devil. With the best intentions, he had interfered just when Luke was losing his self-command and might have said something interesting. "This maidservant who took Mrs. Falkland to visit her mistress—what was she like?"
    A slow grin spread across Joe's face. "Prime little piece, she was. Tall, yellow-haired, with a pretty waist and ankle." 
    "How was she dressed?"
    "Brown-checked frock, I think, sir. And a white cap, with them flaps hanging down on each side. What do you call 'em? Lappets."
    Julian glanced around at the other servants. "Does any of the rest of you know anything about Mrs. Falkland's friend or her maidservant?"
    They shook their heads.
    "Then I have only one more question. Do you recall when this visit to the sick friend occurred?"
    If Luke could remember, he clearly had no intention of saying so. But Joe nodded sagely. "It was the first of April. Sticks in my mind, 'coz the weather was sunny and showery, warm one minute and cold the next, and I said to myself, a typical April day."
    April first. Julian thought back through the calendar. That had been a Friday, so the next day was that first Saturday in April when, according to Nelson, Mrs. Falkland had told Eugene he was to return to school. Something else had happened on April second—what was it? Oh, yes: