Royce went to the wall, as he did many times a day, and scanned the country through his field-glasses. But beyond the Tubus' camps there was nothing to be seen but the vast stretch of open country, dotted with bush and woodland. There were no signs of Challis.

Suddenly he was startled by cries of alarm within the fort. Hurrying in the direction of the sounds, he was amazed to see a cloud of smoke arising from the roofless room used by Kulana. The cook was at the door, groaning and wringing his hands. Others were trying to get through the smoke into the room.

No sooner had Royce reached the spot than he heard new cries and rifle shots from the wall. Thinking that the Tubus were attacking at last, he rushed back to deal with the more pressing danger, leaving the men on the spot to fight the fire.

The Hausas at the north-east corner were blazing away in the direction of the tongue of woodland in which lay the entrance to Goruba's tunnel. But there were no Tubus in sight except a small group on foot far to the left, who were not attacking, but had apparently been drawn from their camp by the sound of firing from the fort.

Yes, there was one other. Looking into the distance he had at first failed to see a dark figure nearer at hand, zigzagging down the lower slopes of the hill. When at last Royce caught sight of it, it was disappearing into the wood.

"Stop firing!" he cried, recognising that it was only a waste of ammunition. "Keep a good look out."

Then he hurried back to deal with the fire, wondering whether the negro he had seen was a scout sent up to reconnoitre the fort.

The fire, meanwhile, seemed to have burnt itself out. The room was still full of smoke, smelling of roasting nuts and grain. Royce was seized with misgiving. He plunged through the smoke, coughing and rubbing his eyes. What he saw filled him with dismay. The whole remaining stock of provisions, except a few tins of beef he kept in his own room, was blackened and burnt.

Running back out of the smoke, he ordered some of the men to save what was still savable, then turned angrily to question Kulana, to whose carelessness he thought the fire was due. But his anger was immediately disarmed, Kulana explained that he had been absent a few minutes, fetching water from the well for the evening meal. The fire was quite safe when he left it, but when he returned the place was in flames.

A new suspicion flashed into Royce's mind. Darting again across the smoke-filled room, he bent down to look through the opening leading to the prisoner's cell. Goruba was gone!