Dr. Glenister had been bending over the body but without touching it. Now she straightened herself and said, “She was strangled by a right-handed grip, the hand probably in a smooth glove. There is bruising by the right-hand fingers and thumb but no nail scratches. I’ll know more when I have her on the table.” She turned to Chandler-Powell. “There’s one question, please. Did you prescribe any sedatives for her yesterday night?”

“I offered her temazepam, but she said she didn’t need it. She had come out of the anaesthetic well, had had a light supper, and now was feeling drowsy. She thought she’d have no difficulty in sleeping. Sister Holland was the last person to see her—apart, of course, from her murderer—and all she asked for was a glass of hot milk laced with brandy. Sister Holland waited while she drank and then removed the glass. It has, of course, now been washed.”

Dr. Glenister said, “I think the lab will find it useful if they could have a list of all the sedatives that you keep in the dispensary here, or any drugs to which a patient could have had access or been given. Thank you, Mr. Chandler-Powell.”

Dalgliesh said, “It would be helpful to have a preliminary talk with you alone, perhaps in ten minutes’ time. I need to get an idea of the layout here and the number and function of the staff, and how Miss Gradwyn came to be your patient.”

Chandler-Powell said, “I’ll be in the general office. It’s inside the porch opposite the great hall. I’ll look out a plan of the Manor for you.”

They waited until they heard his footsteps in the next room and the closing of the corridor door. Now Dr. Glenister took her surgical gloves from the Gladstone bag and gently touched Gradwyn’s face, then her neck and arms. The forensic pathologist had been a notable teacher, and Dalgliesh knew from experience of working with her that she could seldom resist the opportunity to instruct the young.

She said to Benton, “No doubt you know all about rigor mortis, Sergeant.”

“No, ma’am. I know it begins in the eyelids about three hours after death, then spreads down through the face and neck to the thorax, and finally the trunk and lower extremities. The stiffening is generally complete in about twelve hours and begins to wear off in reverse order after about thirty-six hours.”

“And do you think that rigor mortis is a reliable assessment of the time of death?”

“Not entirely reliable, ma’am.”

“Not reliable at all. It can be complicated by the temperature of the room, the muscular condition of the subject, the cause of death, and by some conditions which may simulate rigor mortis but are different—that includes bodies exposed to great heat and a cadaveric spasm. You know what that is, Sergeant?”