The Dark Place

he said. “The fracture occurred while he was alive. Now, how can you tell he didn't die on the spot?'

'If you look at the crack closely—here, use the magnifying glass—you'll see that the edges aren't really sharp. They're slightly rounded because there's been some resorption of the bone. And at the very top of it there's a thin, very slightly raised bead of bone that joins the two edges together. See it? It's a little lighter than the rest of the skull.'

'I see it,” said John with interest. “That shows it's started to heal, right? Which wouldn't have happened if he died right away.'

'Righto. That's point two.'

'All right,” John said approvingly, “but you said you could also tell that he didn't live more than a week longer. How can you...? Ah,” he said, tapping his forehead, “if he'd lived very long, it would be all healed, right?'

'Right. Stick with me; I'll make a detective out of you yet. All right, here comes the third conclusion—that the trephining came after the blow on the head and probably killed him immediately.” Gideon slid the skull a little closer to John. “Now, this is going to take a small leap of faith, you understand.'

'No, it won't. I'm ahead of you. The crack has started to close up, but the hole shows no sign of healing at all. So he must have died as soon as it was made.” John beamed. “How'm I doing, Doc?'

''A’ on logic, ‘F’ on conclusions. A narrow fracture begins to show healing within a few days, but a larger perforation, like this hole, takes longer. In fact, it never actually heals in the sense of closing up; it just rounds the edges. But even that wouldn't begin to show for a while. So even with the lack of visible healing, he could easily have lived another few weeks.'

'So how do you know he didn't?'

'I mentioned septic osteitis a few minutes ago.” Gideon waved his hand as John began to write again. “Don't worry, I'll write it up for you. Septic osteitis is simply inflammation of the bone due to infection. If it had occurred, you'd see a roughening, a pitting of the bone all around the hole. But it's smooth. So, no infection.'

'Okay,” John said dubiously, “but I don't see—'

'As a matter of fact, primitive trephining—with a sharpened mussel shell, say, or a piece of flint—almost always did cause a severe, often fatal infection of the bone. But not here. Therefore, I think we can assume it caused Hartman's death.'

John opened his mouth to speak, looked confused, and closed it again. “Come again?” he finally blurted. “It didn't infect, and so therefore it did cause his death?'

'Right,” Gideon said, smiling at John's expression.

'This must be the place where we make the leap of faith,” John said.

Gideon laughed. “Look, if Hartman had lived, we can assume—say, with ninety percent probability—that the bone would have become infected within a few days. But once bone is dead, it doesn't infect. This bone didn't infect. Ergo; the operation killed him right then, or a day or two later at most.'

Gideon sat back in his chair and drank some coffee, but John leaned forward. “Wait a minute, not so fast. I'll go along with you up to a point: Hartman couldn't have lived long after the trephining, okay—that is, okay with a ninety percent probability. But that doesn't mean the trephining killed him. That's just a guess. There's a big difference between correlation and cause-and-effect.” He grinned. “Want to know who I learned that from?'

'It's a guess, all right,” Gideon said, “but when all you have is dry bones, some educated guesswork is part of the game.” He patted the skull. “Here you have a guy who's dead. Obviously. You examine his remains and you see that, probably on the same day he died, he had a big hole gouged out of his head in an appallingly primitive manner. I'd say you're on reasonably firm ground proposing something more than a chance relationship between the hole and the death.'

'Yeah, but it's still guesswork. It's not proof.'

'Pardon me,” Gideon said with some asperity. “I'm simply trying to make reasoned inferences from extremely limited data. If that isn't good enough—'

'Take it easy, take it easy. God, you're as bad as Fenster.” He laughed suddenly, a childlike peal that crinkled the skin around his eyes into a thousand good-humored folds. “I'm not as used to these leaps of faith as you are. Can I ask a question without getting thrown out of class?'

Gideon smiled. “What?'

'If there's no healing and no septic whatever-it-is, how do you know he wasn't already dead when the hole was made? Didn't you say people used to make amulets out of the piece of bone?'

Gideon tilted the skull so the light slanted across the parietal. “Do you see that hairline crack coming out of the bottom of the hole?'

'I think so,” said John, leaning over the skull. “And isn't this another one, a healed one?” he said, fingering a slender white line that ran an inch into the frontal bone from the anterior border of the hole.

'It is. Three cracks altogether, radiating from the center of the piece of bone that was removed. Doesn't that suggest that the original blow to the head pretty well splintered the bone there? It would have made a pretty lousy amulet.'

'Whew,” said John. “So what does it all add up to?'

'My guess—'

'Your reasoned inference?'

'That's what I said...is that Hartman was hit on the head with something blunt, something like a hammer or the back of a hatchet, resulting in a depressed fracture of the left parietal. When he didn't mend properly—perhaps he never regained consciousness—they tried to relieve the pressure by trephining to remove the sunken fragments of bone. That didn't work and probably set him back, and he died.'

'Who's ‘they'?'