When he reached the flat the sand and mud were soft and his step got labored, but the light was going, he heard ducks, and thought he might get near them in the gloom. They flew off, and he followed some curlews that led him on for a time and then vanished with a mournful cry. Marston stopped and looked about. He had gone far enough, the tide had turned, and it was getting dark. Dark came quickly at the lagoon.
Across the little channel, mangroves rose from sloppy mud. Their roots were five or six feet high, and mudfish splashed in the holes beneath. Crabs crawled about the roots, for he heard their claws scratch on the smooth bark. He knew the noise; one heard it on board the schooner when the tide was low, and Marston hated the hideous mangrove-crabs that swarmed about the lagoon. They were savage and not afraid. If one sat on the sand, they crawled over one's body and their bite was sharp. A curlew's wild cry pierced the gloom and then all was quiet.
Marston frowned. Now the light was going, the forest looked sinister. Perhaps he was imaginative, but his half-conscious shrinking had some grounds. In the tropics the woods were hostile and sheltered man's enemies, of which the insect tribes were perhaps the worst. They attacked in hosts, with poisoned jaws. Then a pale glimmer caught Marston's wandering glance. The tide was creeping across the mud.
He went back and stopped at the bridge. Dark had fallen, but the moon was above the jungle and its light touched the channel. The log ran across like a thin black bar, a few feet above the slime. It looked frailer than when he had come. He braced himself, and balancing carefully, went a yard or two along the trunk. Then he heard a crack and seized the creeper as the log dropped under his feet. He held fast, although the strain on his arm was sharp. There was a splash, the creeper broke, and swinging back with one end, he dropped in the mud. It rose to his knee and for a minute or two he splashed and struggled furiously. Somehow he got out and floundered back to the bank he had left. He was breathless and rather surprised to find he had not dropped the gun, but the arm by which he had hung was horribly sore.
Then it dawned on him that he was on the wrong side of the channel and could not get across. When he fell into the mud he was not far from the bank, but he had gone deep and it was unthinkable that he should venture farther out. The half-liquid mire would suck him down. Still the tide was rising and he could not stop on the flat. After a few moments, another thing struck him; when he crossed, the bridge, although narrow and slippery, was firm, but now it had given way as soon as it bore his weight. The log had slipped down, or broken, suddenly. He wondered whether it had been meant to break. A few strokes with the cutlass the half-breeds carried would be enough, and he could not have struggled out had he dropped where the mud was deep.
Marston clenched his fist and raged with helpless fury. He was persuaded somebody, with devilish cunning, had set the trap for him. When the tide rose the dinghy would drift up the lagoon and in the morning the yacht's crew would find her stuck among the mangrove roots. It would look as if he had landed on a mud bank and had stopped too long. Then, with an effort, Marston pulled himself together. He must search for a place where the bottom was not so soft.
He ran across the flat, heading for the lagoon and hoping he might find a belt of firm sand that would enable him to wade across, but there was none, and by and by he came to the main channel. It was wider and he saw clumps of weed and flakes of foam drift past. The tide was rising and would presently cover the flat. He went back as near as he could get to the jungle, and sitting down with the gun across his knees, took off his shoes. He had sometimes gone wild-fowling on the English coast and knew one can pull one's naked foot out of mud where one's boot would stick. The gun might be an embarrassment, but he meant to keep it to the last, because the fellow who had cut the bridge might be lurking about.
Treading very cautiously, Marston tried the bank again, but began to sink and had some trouble to regain the flat. It was obvious that he could not cross, and he doubted if he would be much better off if he reached the mangroves some distance from the path. The tide flowed back among them, their trunks were slender, and they were haunted by poisonous insects and the horrible crabs. If the crabs attacked him when the tide rose and he was forced to cling to the trees, he could not beat them off. All the same, he could not swim to the schooner.
For a time he wandered up and down the flat. Although he saw no way of escape, he could not keep still. In the end, he must swim, but he meant to wait until the tide drove him off the flat. There was not much use in swimming when one could not find a spot to land. The rising water presently forced him back to the small channel, where he stopped. The moon had got bright and although, for the most part, the mangroves on the other side rose like a dark wall, the silver beams touched their branches here and there. Marston searched them keenly, because he had a strange feeling that somebody was about. Perhaps the fellow who had cut the bridge had stopped to watch him drown.
He thought he heard a soft rustle, leaves moved, and throwing the gun to his shoulder, he pulled the trigger. The barrel jerked, the sharp report rolled across the woods, and leaves and twigs came down; but that was all, and Marston, swinging the gun, pulled the other trigger. Then as the echoes died away he thought he heard a distant shout and a regular throbbing noise. He paused as he pushed in fresh cartridges, and listened hard. The noise was like the splash of oars and got louder. It was the splash of oars, and a shout came across the water again. Marston fired another shot and then waited, trembling with the reaction. Wyndham was coming for him on board the gig and the crew were pulling hard. They would reach him before the tide covered the flat.