"Coming up too fast," Hedi replied.
"Then why didn't Briars have one? He's twenty-five years older than Ron."
"Doesn't matter. Briars probably lost consciousness right away. You're unlikely to have an embolism if you're unconscious. Maybe Ron stayed awake too long."
"Oxygen," the policeman, a man named Ahmed Ben Osman, said the next day. "Apparently that was the problem."
"I thought there was supposed to be oxygen in the tanks," I said, mystified.
"Quite so," Ben Osman said. "But not, apparently, in the quantity that was found. I'm not a diver, but according to an expert we called in, there was way too much oxygen, more than forty-five percent," he added, checking his notes.
"How much is there supposed to be?" I asked.
"About twenty-one percent," Hedi said. "Twenty-one percent oxygen, seventy-nine percent nitrogen."
"Quite so," Ben Osman repeated. "I am told--again, I am not the expert--that at the depths that Mr. Todd and Mr. Hatley were working, this much oxygen is as good as poison. Very little warning of a problem, either."
"So why was there too much oxygen in them?" I said.
"A very good question, Madame McClintoch, and one to which I would like the answer myself," Ben Osman said.
"I don't know how it would have happened. We could check the compressor . . ." Hedi said.
"We are doing that," the policeman said.
"I know that when I tested the mixture after I filled the tanks, everything was okay. That means that the problem occurred after that, overnight. I am really very careful about this, Lara," he said miserably. "I hope you believe me."
"I know you are, Hedi," I said. "Briars does, too. So let's talk about how someone else could have tampered with the tanks overnight. Is it possible to put too much oxygen in the tanks?"
"Sure. I suppose someone could have just let some of the compressed air out of the tanks, take them down to say, a thousand or twelve hundred psi, and then fill them up again with straight oxygen. The pressure would look okay when I tested it."
"Would that be hard to do? Put the oxygen into the tanks? I mean, I wouldn't know how to do it."
"I think it is fair to say most people wouldn't know how to do this," Ben Osman said, looking at Hedi.
"Not difficult, no," Hedi said. "You would need the right equipment, and you'd have to get it out to the boat. We leave the boat at anchor, and come in and out on the outboard. It's cheaper than paying the marina fees. But if you had the equipment, it would be easy enough to do."
"So the pressure would look the same, but the contents of the tanks would be different."
"That's right. And there'd be no odor or anything that would warn the divers there was a problem. You wouldn't even notice it until you got down pretty deep. It would have no effect in those proportions until you got down to maybe a hundred twenty feet."
"That's just about where Briars said he was when he realized he was in trouble."
"This is all very interesting," Ben Osman said. "I suppose it could have been an accident, someone making a very bad mistake, or, and personally I think this more likely, it could be the latest strike in a war between two parties looking for treasure. First, the boat belonging to one of these parties is damaged. The head of this particular expedition blames the other. Several people hear his threats. Then, two days ago, the ship belonging to the other party catches fire. Someone who has the misfortune of being on it, is seriously injured. Yesterday, the scuba tanks belonging to the first group in this dispute, are tampered with. One person is injured, another dies. An eye for an eye, perhaps, but rather upping the ante each time, if that is the correct expression, are we not? You may go now," he said. "We are finished here for the moment. Please send in the next person as you leave."
The next person, as it turned out, was a stocky man with graying hair, a paunch, and a ruddy complexion, in a blue shirt with a star logo. He'd been sitting with his head in his hands as we came out, but looked up at us. He had blood-shot eyes, and his hands were shaking. "You're next, Peter Groves," I said, pointing to the door.
9
W HY DID MEN take others' lives in this way, Hasdrubal wondered, not during the heat of battle, nor from a careless act, but in a cold and calculating manner? Greed, perhaps. No doubt many had died to enrich others, and Mago was not, he thought, above such covetousness, nor moreover, incapable of such a deed. And Safat. Never one to come up with an original idea, yet he could almost certainly be talked into such an undertaking. Love? Yes, perhaps as strong a motive, under certain circumstances, as greed. That would point to Malchus, but only, as far as he knew, where Abdelmelqart was concerned. For Baalhanno, he knew of nothing that would have incited such rage. What else? Revenge. Now there was an obsession that ate at the psyche. Was there someone on the ship who burned for retribution? But surely revenge was linked to the other two. When it came right down to it, were there impulses other than greed and love, in all their aspects, that were powerful enough to warp the human soul? How little he knew, really, about the people on his ship. He'd have to think very carefully, listen attentively to what people said, to see if he could find the viper in their midst. He'd talk to the boy again.
"D OES THIS MEET your expectations, monsieur?" the proprietor asked. "Small, I know, but gold. Pure gold."
Emile turned the coin over in his gloved hand and applied the magnifying glass to it once more.
"Not bad," he said. "I will pay you two thousand U.S. dollars for it."
"That is satisfactory. Would you like more than one of them?" the man said, smiling.
"Are there more?" Emile asked.
"Possibly," the man replied.
"And how many more might there possibly be?" Emile said.
"How many more do you want?" the man said, a sly expression crossing his face.
Emile slammed his fist down on the counter. "Answer the question!" he said.
The proprietor started to sweat. "Three, perhaps four."
"Where did you get them?"
The man hesitated for a moment, and licked his lips nervously.
"Where did you get them?" Emile said again. His voice was deadly quiet.
"I have my sources," the man said.
"I will pay you one thousand each for four of them, and only if you sell all that you have to me."
"But, monsieur," the man said. "You offered two thousand dollars. You must pay me two thousand dollars each."
"One thousand each," Emile repeated, and wrote something down on a piece of paper. "You can reach me at L'Auberge du Palmier," he said, handing the man the slip of paper. "I will only be here for a few more days."
"Monsieur," the proprietor said, looking pained. "I am not the expert in numismatics you are, of course. But I have books--" He gestured to a dog-eared row of catalogues behind him. "I know there are very, very few of these coins in existence. This coin is very rare, and worth more than one thousand dollars."
"Not anymore," Emile said. The man looked perplexed. "Think about it," Emile said softly.
"I hate being ripped off," he said to me as we left. "Particularly by amateurs."
"I gather, though, that this fellow is more interesting to you than the last one," I remarked.
"Somewhat," he said. "Now let's try to find those tables you need."
M Y EXPERIENCE OF group travel, limited though it may be, is that there comes a point in every tour where the members of the group begin to feel like old friends. Bonding, I think the psychologists would call it. Perhaps it's just from being so far from home and their real friends, or maybe it's the mutual attraction of like-minded people in a very different--and perhaps threatening, just because it's so different--part of the world. Whatever the reason, they begin to tell each other things about themselves that I am convinced they would never share with such relatively casual acquaintances at home. I could see it happening in my group. But troubled by my suspicions and traumatized by the dreadful happenings of the day before, I did not want to be close to any of them, and felt their confidences something to be endured rather than enjoyed. Indeed, by midafternoon of the day after the diving incident, I was rather uncharitably beginning to feel as if there were a flashing neon sign over my head, visible to everyone but me, that said The Doctor Is In."