No well-trodden path led to the lake side. The men had had to make a way for themselves through the underwood. On reaching the edge they came upon clear signs of human activity--a rough landing-stage of boards, litter and debris of all kinds. But no human being except Tom's own men was in sight, nor, so far as could be ascertained, was any boat moored along the shore, though the banks of reeds might well conceal many craft.
"Mbutu," said Tom, "clamber up that tall tree and tell me what you see."
Mbutu, agile as a monkey, was soon swarming up a straight trunk.
"I see a boat!" he cried, when he came near the top. "Long, long way; go dis way"--he waved his arm from east to west. "Go from shore to island. Small canoe; four men. No more, sah."
Tom called up a prisoner, and, questioning him, learnt that the canoe was probably crossing at the shortest passage, requiring only half the time that would be taken from the point at which the expedition had struck the lake.
"Anything more to be seen, Mbutu?"
"No, sah, nuffin."
"Come down, then; we'll have to do a little scouting."
A path ran round the lake close to the edge, narrow and much overgrown, but evidently leading to the spot from which the canoe had started for the island. Tom sent fifty of his best scouts, under Mboda, to explore this path.
"If you come across any canoes, seize them," he said. "Don't fight if they are defended in force; they probably won't be worth losing lives for."