For the second boat had suddenly been swept from her anchorage and come rapidly down upon the first. The men tried their hardest to ease her off, but she came into collision with so sharp a shock that the bigger boat was jerked free from her moorings and began to glide with the swift current, dragging her grapnel after her, till the captain gave orders for it to be hauled in.

“Row!” he shouted, and the men dipped their oars into the water with a steady stroke, keeping the boat’s prow head to stream as she dropped down stern foremost between two mighty walls of verdure, while on either side it was plain to see that the trunks of the huge forest monarchs were being flooded many feet up.

“There’s nothing else for it, sir,” said the captain to Sir Humphrey. “You’ll be seeing what the country’s like, and by-and-by as the water drains off I daresay we can ride easily back with the current quite the other way.”

“And what about capsizing?” said Briscoe.

“That’s my look-out, sir,” said the captain gruffly. “Capsizing means feeding the fish, and I’ve a great objection to being used for that purpose, without taking into consideration my duty to my passengers and men.”

He met Brace’s eyes as he spoke, his own twinkling with a drily humorous look, and nothing more was said.

The adventure was exciting enough, for the boats rode on rapidly through the forest, the river, which was comparatively narrow, winding and doubling in the way peculiar to water making its way through a flat country. For now all appeared to be one dead level, with the trees on either side much of a height. Every now and then it was as if they had been swept by the heavy stream into a lake whose end was right in front, but invariably as they were gliding straight for a huge bank of trees the river curved round to right or left, opening out into some fresh bend of its serpentine course, but there was no alteration in their rate of speed.

“It can’t last very much longer, though,” said Briscoe. “Why, we’re going along just like two corks in a gully.”

“Yes,” said Brace, who had been watching the movements of a troop of monkeys passing along through the trees on their left. “It’s all very well now, but if this is to go on after dark we are bound to come to grief.”

“No,” said Briscoe drily. “The skipper won’t risk it. He’ll pick his place and run us in among the tree-trunks before sunset. He’s a dry old chap, but the longer I’m with him the safer I feel.”