“That's sound, I believe,” Sir Clinton acquiesced. “She swallowed the stuff at Heatherfield before going out. Now who are your three suspects?”
“Mrs. Silverdale herself might have taken it, sir, either on purpose or by mistake.”
“But she had no access to hyoscine that we know of.”
“No, sir, but both Silverdale and young Hassendean had. She may have taken it in mistake for a headache powder or something of that sort. And it might have been added to a headache powder by either Silverdale or young Hassendean.”
“That's a good enough suggestion, Inspector. But I didn't see any sign of a powder paper in her room when I searched it; and you remember she came straight downstairs and went out of the house, according to the maid's evidence. Any other view?”
“Then it must have been administered in the coffee, sir, by either young Hassendean or the maid.”
“The maid? Where would she get hyoscine?”
“From Silverdale, sir. It's just occurred to me. Silverdale wanted a divorce; but he couldn't get evidence because his wife was simply playing with young Hassendean and keeping well within the limits. But if she were drugged, then young Hassendean might seize the chance that was offered to him, and if Silverdale was prepared beforehand, he'd have his evidence at the cost of watching them for an hour or two.”
“So Silverdale gave the maid the drug to put in one of the cups of coffee and ordered her to give that cup to Mrs. Silverdale, you think?”
“It's possible, sir. I don't put it higher. That maid was a simple creature—look how the doctor pumped her on the pretence of getting medical information that night. She was devoted to Silverdale; he told us that himself. She'd swallow any talk he chose to hand out to her. Suppose he faked up some yarn about Mrs. Silverdale needing a sedative but refusing to take it. The maid would believe that from Silverdale, and she'd put the hyoscine into the cup quite innocently. If the worst came to the worst, and the cups got mixed, then young Hassendean would get the dose instead.”