"That settles it, I think," said Lionel. A projecting snout rose at the box, tilting it over. It fell back, lipping under, so that it filled. In another instant it was gone from sight. The glasses showed a slight swirl in the water. The swirl passed at once, under the drive of the spate. Their last hope of atoxyl was at an end.
"Well," said Roger hopelessly. "It's as well to know the worst. The box was empty, don't you think?"
"I don't know," said Lionel. "I couldn't be sure."
"We might find some things in the water when the river sinks a little further," said Roger, without much conviction. "It'll be drying up very soon now. Then we shall find whatever is in it."
Lionel sat down despondently, resting his chin on one hand. He was letting his disappointment work itself off silently. His heart had been set so long on this first great medical field-day that he could not look Roger in the face. The loss of the atoxyl was less hard to bear than the loss of all the interesting cases over which he would have been bending at that minute had this ghastly thing not happened. And, being an old campaigner, and therefore forethoughtful, it was bitter to him to find himself thwarted unexpectedly by a trick so simple. He had thought that he had guarded against all the known dodges. He had been on his guard all through. In London he had sampled the food, the clothes, the cartridges, rejecting everything which seemed even faulty. He had been surprised at his own strictness. All the way up from the coast he had watched his stores so jealously that he had thought himself safe. He had been vain of his success. He had never lost so little in any previous expedition. Now an attack of fever, a storm, and a bearer's sudden death had let him in for this. He was not forgetting the chemist's share. He cursed himself for having trusted the chemist. Then he decided that it was not the chemist. The fraud had been committed in Africa. He had not been careful enough. He himself was to blame. "Guns and grub I could understand," he cried. "But for them to take drugs! Who would have thought of their taking drugs? Why didn't I see that Africa is getting civilised? Roger, I want to kill somebody."
"It's my turn to lecture now," said Roger. "We'll carry these things up to camp. I've an idea about camp."
"What is your idea?"
"To build a house out of the loose stones of the wall. We could use the wall itself for one wall, build up three others and roof it with the tent. It would be better than having another night like last night."
"It might be done," said Lionel, mechanically filling his pockets with cartridges. "But I don't know what good we're going to do here if we haven't any atoxyl. I wish I knew who it was. If ever I touch at Kwasi Bembo again, I'll have that atoxyl out of his liver."
They passed a broiling afternoon carrying their gear to camp. They became irritable at about four o'clock. After that time they worked apart, avoiding each other. At six Roger made tea, over which they made friends. At seven they set about the building of their house. They laboured by moonlight far into the night, laying the mortarless stones together. When they knocked off for bed it was nearly midnight, and the house was far from perfect. They could not do more to it. They were too tired. After flogging their blankets against the walls to get rid of mud and "bichos," they turned in, bone-weary, and slept the stupid sleep of sailors for nearly eleven hours.