daggerbut it could be something quite different. Of course, this is no plaster cast.'
Thora and Matthew stretched over for a better look at the photograph. The doctor was right. A mark left by an indeterminate object was clearly visible on his neck. A scale at the bottom of the photograph showed that the object was eight to ten centimeters long and the outlines up the neck bore a fairly close resemblance to a small dagger or cross. 'What's that?' Matthew asked, pointing to abrasions on either side of the mark.
'Something with sharp edges appears to have been behind the small object. These punctured the skin when the strap was tightened. That's the closest I've got.'
'What happened to the belt or whatever it was?' Matthew asked. 'Was it ever found?'
'No,' the doctor replied. 'The attacker got rid of it. He doubtless thought that we could have obtained a DNA sample from it.'
'Could you?' asked Thora.
The doctor shrugged. 'Who knows? But if it were found now, so long after the incident, the samples wouldn't be reliable.' He cleared his throat. 'Then there's the estimated time of death. That's a much more technical issue.' The doctor flicked through the documents and removed several pages. 'I don't know how familiar you are with such procedures, in terms of how we determine it?' He looked at Thora and Matthew.
'I have no idea,' Thora said quickly. She saw that this annoyed Matthew, who did not say a word, but that didn't bother her.
'I suppose I should explain briefly what it entails so that you realize the results are neither some kind of magic nor irrefutable fact. They only express probability because the accuracy of the result depends on the accuracy of various information or clues that need to be collected.'
'Collected?' repeated Thora.
'Yes, to make such an estimate we need to collect clues that can be found on or near the body itself and in its surroundings. We also make use of clues from the life of the deceased, for example, the last time he was seen before his death, when he last ate, his habits, and the like. This is especially important in the case of violent deaths like this one.'
'Of course,' said Thora, smiling at the doctor.
'The information or clues are then applied in various ways to produce the best estimate of the time of death.'
'How?' Thora asked.
The doctor leaned back in his chair, clearly pleased at the interest she was taking. 'There are two methods. The first is based on measuring changes in the body that take place at a known rate, such as rigor mortis, body temperature, and decay. The other method involves comparing information with known times: when the deceased ate the food that is in his stomach, how it has been digested, and so on and so forth.'
'When did he die?' Matthew got straight to the point.
'That's the big question.' The doctor smiled. 'To pick up where I left off, I should tell you first about the information that we used to estimate the time of death. I don't remember whether I mentioned it, but the sooner the body is found after death, the more reliable the clues are. In this case the interval was a day and a half, which is not so bad. And because the body was indoors, the ambient temperature is a known value.' He opened the yellow folder and glanced at the text on one of the pages. 'According to the police investigation, Harald was last seen alive by an impartial witness at 23:42 on the Saturday night when he allegedly paid for and got out of a taxi on Hringbraut. You can call that the
He paused and looked at them both. Thora nodded to show that she followed and he should continue. Matthew was statuelike, as ever.
'When the police arrived on the scene following the discovery of the corpse, the body temperature was measured immediately and it turned out to be the same as the ambient temperature. That indicated that some time had elapsed since his death. The exact rate depends on various factors; for example, it happens faster for a thin person than a fat person who has a proportionally larger surface area of thermal emission.' The doctor gesticulated. 'It also depends on the clothing and state of the body, its position, and the air currents, humidity, and various other factors. Information about all of these things adds to the clues I mentioned.'
'And what came out of all this?' Matthew asked.
'Nothing really. It merely enabled us to narrow down the time frame a little. This method can obviously only provide us with information about the time of death if the body temperature differs from the ambient temperature.' He sighed. 'After the body temperature has reached the ambient temperature it remains there, understandably. But we can calculate how long it takes the body to reach that temperature, and infer that as the minimum time since death occurred.' He looked down the page. 'Here it is. In this case the analysis narrowed down the
'This is all very interesting, no question of that,' Matthew said. 'But I would like to know when Harald is thought to have died and how it happened.' He did not look at Thora.
'Yes, of course, sorry,' the doctor said. 'Rigor mortis indicated that the death occurred at least twenty-four hours before the body was found, which narrows the time frame even further.' He looked at Matthew and Thora in turn. 'Do you want me to go into detail about rigor mortis? I can give a brief explanation if you want.'
'Please do,' said Thora, at exactly the same time as Matthew said: 'No, there's no need for that.'
'Isn't it etiquette to allow the lady to decide?' The doctor smiled at Thora. She beamed back at him. Matthew gave her a sideways glance, quite a grumpy one as far as Thora could see. She ignored it.
'As its name suggests, rigor mortis is the stiffening of the body after death. The condition is caused by chemical changes in muscular protein following a reduction in the acidity of muscle cells after death. No oxygen, no glucose, and the pH of the cells drops. Then when the volume of ATP nucleotide falls below a critical threshold, rigor mortis sets in, because ATP prevents the actin and myosin from bonding.'
Thora was about to ask more about this interesting actin and myosin but quickly restrained herself when Matthew deliberately stepped on her foot. Instead, she simply said, 'I understand,' which of course could not have been further from the truth. Out of the corner of her eye, she saw Matthew the statue smile for the first time that morning.
The doctor continued. 'Rigor mortis begins in the muscles that are used most and gradually spreads to the rest. When it reaches a peak the body becomes stiff, remaining in the position it was in when the rigor mortis became dominant. That stage does not last long because rigor mortis wears off and the body relaxes again. Under normal conditions rigor mortis is complete twelve hours after death, then begins to wear off after thirty-six to forty-eight hours. However, in a case like Harald's, where the cause of death is asphyxiation, the process begins somewhat later.' The doctor looked through the papers, took out a photograph and showed them. 'As you can see, Harald's body was totally stiff when it was found.'
Matthew beat Thora to the photograph. He looked at it without a flicker of emotion, then handed it to her. 'It's quite disgusting,' he said as she took it.
'Disgusting' was not a strong enough word to describe what Thora saw. The picture showed the young man whom Thora knew from family photographs as Harald Guntlieb lying on the floor in a peculiar position she recognized from the photographs in the case file. But those had been so grainy and badly reproduced that they were almost fit to show on children's television compared with what greeted her eyes now. One of Harald's arms stood straight up from the elbow, as if pointing at the ceiling. There was nothing to keep the arm in that position or support it. Nonetheless, it was evident from the photograph that Harald Gottlieb was dead. His face was swollen, bloated, and strangely colored, which Thora knew was not because the photograph had been poorly developed. Yet what disturbed her most was the eyes; or, more precisely, the eye sockets. She hurriedly returned the photographs to Matthew.
'As you can see, the body was probably resting against something and the hand became stuck in that position. You doubtless know that the murder was not committed in the corridor. He fell out of an alcove when one of the lecturers opened the door that Monday morning. Judging from his account, the body had been hidden there and either fell against the door or was arranged to fall when the door was opened. As the photo shows, the alcove door opens out into the corridor.'
Matthew scrutinized the photograph, then nodded without saying a word. Thora made do with that; she had no desire to see it again. 'But you haven't told us when you think he died,' Matthew said, handing him back the
