"Stay on for a couple of days," she said. "I'd like that. Take it easy."

INVARIANTS AND HOMEOMORPH.

After a storm the beach has always changed slightly in some way-the sand washed away here to reveal the rocks beneath, then piled up in a swelling dune four hundred yards away. Once, on what had been a wide flat area, a small lagoon formed for a week or so, about sixty feet long behind a solid sandbar. Then came another high tide with a strong wind and the next morning it was gone. The geography of the beach is always changing, yet it always remains the same.

When I asked John why he had moved from turbulence to topology be told me that it was because he was tired of change, and wanted now to study concepts of permanence. He wanted to look at what remained constant in an object, regardless of the force or scale of its transformation. When something is bent, stretched or twisted, be said, certain features of it resist deformation. He wanted to investigate these unchanging features. He told me the name that was given to them: topological invariants.

Throw a pebble in a pond and watch the ripples spread. To most people the widening circles would represent change. But to a topologist, John said, a widening circle is a symbol of constancy. A circle is a closed curve; that is its topological invariant, no matter how it grows or shrinks. I want to look at things that endure, he said, even though everything else about them is changing.

The beach endures, I think as I wander along its length, as well as changing all the time. What is its invariant?...In the palm groves I see two old women from the village gathering fallen coconuts.

In topology, objects that have the same invariants are regarded as equivalent, no matter how different they may appear when looked at. The crumpled disc of a deflated football has the same invariants as an inflated one, even though they look and perform quite differently. Objects that possess this equivalence are known as homeomorphs.

I stroll up into the palm grove and greet the old women. They return my greeting. Here we are, I think, three homeomorphs.... Yes, it seems to me we share the same invariants. The differences between us are superficial. The women smile modestly at me as I say goodbye and continue on my way, then they stoop and begin to gather their windfalls again.

I sat patiently in my room waiting for reception to call and tell me that Hauser had arrived. I had received a message from Grosso Arvore: Hauser was coming to collect me and drive me back to the camp so that the "terms of my contract could be discussed." I was not at all sure what this meant or implied and not very keen, either, to return; but I knew it could not be postponed indefinitely; I had to go back if only to collect my few possessions.

There was a knock at the door. It was one of the assistant managers, a young Ghanaian called Kwame. He informed me that the hotel was clearing out Mr. Shoukry's room, and the manager wondered if there was anything I might like to keep as a memento. I was surprised at such thoughtfulness. As we left the room the phone rang: Hauser was waiting in the lobby. He could wait a little longer.

I stood in Usman's sitting room looking about me, feeling a little uncertain and troubled. Kwame waited discreetly at the door and behind him stood a couple of chambermaids with cardboard boxes and plastic bags.

I went to the desk and opened a drawer. I saw Usman's passport, some documents, some loose change. Nothing for me here. In the bedroom I opened the cupboard. His few clothes hung above four pairs of shoes. I felt strangely panicked. I knew I should take something, that I'd regret it later if I missed this opportunity. But what? I slid the hangers to one side. Did I want that linen jacket? Those ties?...A sudden sensation of nausea overcame me. The whole idea of a memento-a thing-as a substitute for Usman seemed a gross indignity. I pushed another hanger: his official air force uniform, issued to all the pilots, which they never wore. On the shelf above, I saw his peaked cap still in its plastic wrapping and beside it the stiff glossy leather of his belt. The belt? Something useful, at least, that I could wear. I reached up and took it down.

Clipped to the side of the belt was a neat brown holster. The leather was molded into the shape of a stylized kidney. I unclipped the flap. The holster held his small, compact Italian automatic pistol. I took it out and weighed it in my hand.

I thought, with a sudden wrenching inside me, of Usman in his swimming shorts, that day at the airport, showing me his plane so proudly.

His good luck charm, he had said. Why hadn't he taken it with him? I thought, angry now.

My fingers traced his initials on the butt.

I knew at once this was what I wanted to keep. I slid it into my pocket and walked back to the sitting room. It was a foolish thing to do, I told myself, but I had wanted it, the impulse to take it had been powerful. It was the only object in that entire bungalow that brought an image of Usman Shoukry back to me. But I continued my search of the room, however, for form's sake.

Opening a cupboard in the sitting room I came across a cardboard box full of the equipment Usman had used for the construction of his horsefly airplanes: scalpels and razor blades, a fly-tier's vise, slivers of matchwood and balsa, the almost weightless, translucent tissue paper. That sent me back to the desk again, and in a bottom drawer I found a thin file full of delicate drawings of his prototypes. I told Kwame this was what I wanted. As I left the room the chambermaids sidled meekly in.

"You do look well," Hauser said again. "No, really well. I mean, you'd never believe..."

"I feel fine. I'm well rested. Nothing terribly dramatic happened."

We had been driving for over an hour. Hauser, to my surprise, had kissed me on both cheeks when we finally met up in the lobby of the hotel. He had looked pleased to see me and was full of compliments. We had conversed carefully at first, diplomatically avoiding contentious subjects, but I could sense the questions massing eagerly in his head. I decided to confront a few of them.

"How's Eugene?" I asked, disingenuously.

"Ah," Hauser began, his glee almost shamefully evident. He collected himself and made his face solemn. "Good point. Not very well. No, he hasn't been well. Since you left. We've seen very little of him." He glanced at me. "Ginga's been more or less running things. I think Eugene..." he paused, choosing his words, "has had something of a, a nervous collapse. Nervous exhaustion, Ginga says."

"Well. That's reasonable, I suppose."

"What happened?"

"When?"

"That day you left. What went on, Hope? Come on." He smiled at me. "You can tell Anton, surely."

"Well...I'm not so sure."

"Everything's changed. The book's postponed. The feeding area's been closed down. What did you do to him?"

"We had an argument."

Hauser looked at me skeptically, and saw I was going to say nothing more for a while. He carried on talking.

"Of course the whole place has been in uproar since you were...taken. Now that you're safe, and Ian's back, we're almost back to normal. But it's been odd."

"How's Ian?"

Hauser grimaced sympathetically. "He's been trying not to show it but I think he was, you know, traumatized. Poor boy." He glanced at me again. "I mean compared to you he definitely is traumatized."

"Appearances can be misleading."

Hauser laughed. His laugh was high and staccato. "No, no, Hope," he said. "No, no. You're made of sterner stuff."

His amusement was annoyingly contagious, and I found myself smiling back at him. Why had I disliked Hauser so, all these months? The tyranny of first impressions, I supposed. But then I thought back to the incident of the half-eaten baby chimp. I should be more cautious.

"Why have they closed the feeding area?" I asked.

"You're kidding?"

"What?"

"They must have told you. The war. The chimpanzee wars they're calling them. The northern chimps-they've been systematically killing the southerners." He looked for my reaction. "You do know."

"I discovered it."

There was a long pause. Hauser ducked his head, as if apologizing.

"Eugene discovered it," he said.

"No."

"That's why the book is being rewritten."

"I discovered it. That's why I had to leave."

"Look, we all know it was during those days he was out in the field with you. But-" He paused and then said slowly, "Eugene was the one who realized what was going on...."

"I'd been telling him about it for weeks."

Hauser frowned. "That's not the way-how can I tell you?-that events are being presented at the camp."

I felt a tightening in my head, as if a belt were being cinched around my skull. "Jesus Christ."

"I'll be honest. Every one assumes Eugene had made...made some sort of sexual advance to you."

"For God's sake!"

"We don't know anything. We see you run off. Eugene effectively disappears. Ginga takes control. You know..."

"Well, you assumed completely wrong."

"I'm sorry. I'm pleased to hear it."

"Ask Ian. He'll tell you. I spotted this weeks ago. Mallabar wouldn't listen." I looked at Hauser. "Hasn't Ian said anything?"

"Well, no.... He's not really been working."

"Good old Ian."

I turned on Hauser with some of my old hostility.

"Anyway, you should know, too. Incinerating that baby chimp."

"Baboon.... No, Hope, I swear. It was a baboon. We were both wrong."

I looked out of the window at the passing scrubland. A nice irony. A sense of frustration was building inside me that was making my shoulders hunch and my scalp crawl.

"Anyway," Hauser said, his voice placatory, "it'll be great to have you back. We've got two new researchers, but we still miss you, Hope. Really."

The last thing you learn about yourself is your effect. I turned to him. "Unfortunately I don't think I'll be staying long, somehow."

It was unsettling to be back at Grosso Arvore: the place appeared to me simultaneously familiar and strange. We arrived at dusk. The blurry glow of the hurricane lamps shone from the canteen. We went straight in to eat, and Hauser introduced me to the two new researchers-young men, Americans, from Cornell University-who were living in my rebuilt tent-hut. I ate my meal quickly and then went to the census hut to pack up my few possessions. There had been no sign of Eugene and Ginga Mallabar, nor of Ian and Roberta Vail.

I sat on my bed in the long gloomy room thinking about the low-key, not to say nonexistent, welcome I had received. Only Hauser and Toshiro had seemed pleased to see me. More beds had been moved into the hut since I had last been here, and the framework of a partition had been erected that would eventually divide the room. Good times were returning to Grosso Arvore, that much was clear.

I sat on my bed and allowed my swiftly alternating moods to dominate me, unchecked. I felt by turns apathetic, sullen, hard done-by, bitter, frustrated, baffled, hurt and, finally, contemptuous and independent. Mallabar, "nervous exhaustion" or no, was evidently trying to initiate some sort of damage limitation program, to incorporate my discoveries about the chimpanzees into his magnum opus before it was too late. I began to regret my hasty note informing him of my own publishing plans.

There was a quiet knock at my door. Ian Vail, I thought, as I went to answer it, and about time too. But it was Ginga. She embraced me, inquired about my health and state of mind and complimented me on my fresh and calm demeanor.

She was wearing jeans and a dark blue cotton shirt. Her hair was held back from her seamed, sharp face by a velvet band. She looked fresh and calm herself, I thought.

"How's Eugene?" I asked.

She paused before she answered, looking down at the floor.

"He never told me what happened that day," she said.

"He tried to kill me." I paused. "I think."

Ginga looked away with an abrupt jerk. She put both hands to her forehead and smoothed it. "I can't believe that," she said.

"He went mad, sort of. He hit me. Violently. If I hadn't run away..."

Now she was looking fiercely at me again, as if gathering reserves of energy and determination within her. Then she said, in a quiet voice, "You must understand what this has done to him, Hope, the killings. The attacks, you must try."

"Look, I told him. He didn't want to hear about it. I wasn't trying to...outsmart him, or anything."

"I know, I know. But that didn't make it any less hard on him. And the fact that someone like you-I mean, a new arrival-should..." She made a flicking gesture with one hand. "Should turn everything upside down."

"I suppose..." I checked my spontaneous British reasonableness. No lifelines were going to be offered here.

"He's not well," Ginga went on. "Very depressed. It's difficult."

"I'm sorry," I said. "Can I see him?"

Ginga looked suddenly ashamed, all her poise and cool capability gone. I had never seen this emotion on her features before; it looked absurd, wholly out of character, like a false mustache or a clown's red nose.

"He won't see you," she said. "He refuses."

"Oh, great.... So where does that leave me?"

Ginga's composure had returned. "Well, you understand...it's impossible to work on here, my dear."

I closed my eyes for a second or two, then stood up and wandered round the room, behaving as if I had some choice in the matter, as if this were a decision that had to be mulled over, thought through. Ginga waited with perfect patience.

"You're right," I said. "It's impossible. Under the circumstances."

"I thought you'd agree."

She took some papers out of her bag and laid them out on the desk.

"It's just a formal letter of release. If you could sign there.... And I have a check"-she tapped an envelope-"for what is due you for the rest of your contracted period of employment."

"Very generous of you."

She responded sharply to my sarcasm. "This is nothing to do with me, you know, Hope. We're friends, or so I like to think. But that doesn't matter. I have to help Eugene. Grosso Arvore has to keep going. Without him...well, you know how the place works."

I wondered seriously, for the first time, about the true extent of Mallabar's nervous exhaustion.

I signed. Ginga smiled at me, sadly, I thought.

"There's one more thing," she said. "I'm very sorry."

"What?"

"This is your original contract." She turned some pages of the document. "Do you remember this clause?"

I read it. I had to smile. All publications, its gist ran, based on original research carried out at Grosso Arvore, were the copyright of the Grosso Arvore Foundation, unless alternative permission was given. All data gathered was similarly protected and had to be surrendered to the foundation for its archives on termination of employment.

"No," I said. "You can't do this. Forget it."