De La Rey has judged it finely. Centaine could barely contain her relief. She had guessed right. Lothar was heading for the Portuguese border after all.
He and the diamonds were not far ahead of them.
How long, Kwi? she demanded anxiously, springing down to examine the spoor for herself.
This morning, Nam Child, the little Bushman told her, pointing to the sky, showing where the sun had stood when Lothar passed.
Just after dawn. We are eight hours or so behind them, she told Blaine.
That's a lot to make up. He looked serious. Every minute we can save will count from now on. Troop forward! When they were half a mile from the hillock with its kokerboom crest, Centaine told Blaine, 'There have been other horses grazing around here. A large troop of them over many weeks. Their sign is everywhere. It was just as we guessed, De La Rey has had one of his men herding them here. We should find further evidence of that at the waterhole. She broke off and peered ahead. There were three dark amorphous heaps lying at the base of the hill.
What are they? Blaine was as puzzled as she was. Only when they rode up did they realize what they were.
Dead horses! Centaine exclaimed. De La Rey must have shot his used-up horses. No. Blaine had dismounted to examine the carcasses. 'No bullet holes. Centaine looked around. She saw the primitive stockade in which the fresh horses had been kept awaiting Lothar's arrival and the small thatched hut where the man left to tend them had lived.
Kwi, she called to the Bushman. Find the spoor going away from here. Fat Kwi, search the camp. Look for anything which will tell us more about these evil men that we are chasing. Then she urged her gelding towards the fountain head.
It lay beneath the hillock. Subterranean water had been trapped between strata of the impervious purple shale and brought to the surface here. The hooves of wild game and the bare feet of San people who had drunk here over the millennia had worn down the shale banks. The water lay fifteen feet down in the bottom of a steep conical depression.
On the side nearest the hillock a layer of shale overhung the pool like the roof of a verandah, shading the water from direct rays of the sun, cooling it and protecting it from rapid evaporation. It was a tiny clear pool, not much larger than a bath tub, fed constantly by the up welling from the earth.
From experience, Centaine knew that it was brackish with dissolved minerals and salts, and strongly tainted with the droppings and urine of the birds and animals that drank from the spring.
The pool itself held her attention for only a second, and then she stiffened in the saddle and her hand flew to her mouth, an instinctive expression of her horror as she stared at the crude manmade structure that had been erected on the bank at the edge of the pool.
A thick branch of camel-thorn had been peeled of its bark and planted in the hard earth as a signpost. At its base rocks had been piled in a pyramid to support it, and on its summit an empty half-gallon can had been placed like a helmet.
Below the can a plank was nailed to the post, and on it were burned black charred words, probably written with the tip of a ramrod heated in the fire:
THIS WELL IS POISONED
The empty can was bright red with a black skull and crossbones device and below that the dreaded title:
ARSENIC
Blaine had come up beside her and they were both so silent that Centaine imagined she could hear the shale beneath them ticking softly like a cooling oven, then Blaine spoke: The dead horses, he said, 'that accounts for it. The dirty bastard. His voice crackled with outrage. He pulled his horse around and galloped across to join the troop. Centaine heard him calling, Sergeant. Check the water that is left. The well is poisoned, and Sergeant Hansmeyer whistled softly.
Well, that's the end of the chase. We will be lucky to get back to Kalkrand again. Centaine found she was trembling with anger and frustration. He is going to get clean away, she told herself. He has won on the first trick. The gelding smelled the water and tried to get down the bank. She forced him away with her knees, slapping him across the neck with the loose end of the reins. She tethered him at the end of the horse line and measured a ration of oats and mash into his nose bag.
Blaine came to her. I'm sorry, Centaine, he said quietly.
We'll have to turn back. To go on without water is suicide. I know. It's a pretty filthy trick. He shook his head. Poisoning a water-hole that supports so much desert life. The destruction will be horrible. I have only seen it done once before.
When we were on the march up from Walvis in 1915, he broke off as little Kwi came trotting up to them chattering excitedly. What does he say? He asked.
One of the men we are following is sick, Centaine answered quickly. Kwi has found these bandages. Kwi had a double handful of stained and soiled cloth which he offered to Centaine.
Put them down, Kwi, she ordered sharply. She could smell the pus and corruption on the bundle. Obediently Kwi set it down at her feet, and Blaine drew the bayonet from its scabbard on his belt to spread the strips of cloth on the sand.
The mask! Centaine exclaimed, as she recognized the flour sack that Lothar had worn over his head. it was stiff with dried blood and yellow pus, as were the strips torn from a khaki shirt.
The sick man lay down while the other changed the saddles to the new horses, and then they had to lift him to his feet and help him to mount. Kwi had read all this from the spoor.
I bit him, Centaine said softly. While we were struggling I sank my teeth into his wrist. I felt the bone. it was a very deep wound I gave him. A human bite is almost as dangerous as a snake bite, Blaine nodded. Untreated it will nearly always turn to blood-poisoning. De La Rey is a sick man, and his arm must be a mess, judging by these. He touched the reeking bandages with the toe of his riding-boot. We would have had him. In his condition, we would almost certainly have caught him before he reached the Okavango river. If only we had enough water to go on. He turned away, unwilling to watch her unhappiness, and he spoke sharply to Sergeant Hansmeyer. 'Half water rations from now on, Sergeant. We will start back to the mission at nightfall. Travel in the cool of the night. Centaine could not stand still. She whirled and strode back towards the water-hole, and stood at the top of the bank staring at the notice board with its fatal message.
How could you do it, Lothar? she whispered. You are a hard and desperate man, but this is a dreadful thing, She went slowly down the steep bank and squatted at the edge of the water. She reached out and touched the water with her fingertip. It was cold, cold as death, she thought, and wiped the finger carefully on the leg of her breeches as she stared into the pool.
She thought about Blaine's remark, I have only seen it done once before. When we were on the march up from Walvis in 1915, and suddenly a forgotten conversation sprang up from deep in her mind where it had lain buried all these years. She remembered Lothar De La Rey's face in the firelight, his eyes haunted as he confessed to her.
We had to do it, or at least at the time I thought we did.
The Union forces were pressing us so hard. If I had guessed at the consequences, He had broken off and stared into the fire. She had loved him so dearly then. She had been his woman. Though she did not yet know it, she already had his child in her womb, and she had reached out and taken his hand to comfort him.
It doesn't matter, she had whispered, but he had turned a tragic face to her.
It does matter, Centaine, he had told her. It was the foulest thing I have ever done. I returned to the water-hole a month later like a murderer. I could smell it from a mile or more. The dead were everywhere, zebra and gemsbok, jackals and little desert foxes, birds, even the vultures that had feasted on the rotting carcasses. So much death. It was something that I will remember on the day I die, the one thing in my life of which I am truly ashamed, something I will have to answer for. Centaine straightened up slowly. She felt her rage and disappointment slowly snuffed out by a rising tide of excitement. She touched the water again and watched the circle of ripples spread out across the limpid surface.