"Well?" he demanded curiously. "You've found something? What is it?"
"Reckon dem 'ere blackguard run in here full tilt, I do. Dey come whop up agin de tree, and precious nigh upset. Dere's a dent right here big enough to put de hand in. Stop a minute. Sam soon say if dey passed."
Without waiting for his master, he slipped into the water, to discover it deep enough almost to submerge him. But Sam was more like a fish than anything. He struck out for the tree, reached it, and clambered down towards that portion which seemed to have sunk deepest. In the gloom they saw him stretching out a hand to the opposite bank. He gripped a branch hanging conveniently overhead, and then swung in the water.
"Dey come right along plump in here," he sang out "Den dey sheer off, and steam in alongside. Jest room enough. See here, Massa Jim, plenty space to swing de legs. Plenty room to float de launch; but I make extry sure. Yo see in one little bit."
They heard him splash down into the stream, while there came to their ears the swish of the branch suddenly relieved of his weight. Then the fitful rays played upon the splashes as the negro breasted the water and swam upstream. Presently the swish of his strokes ceased, and his voice was heard again, some little distance inland.
"Yo kin jest steer to de right ob dat stump, yo can, Massa Jim. Plenty water. Reckon dem scum come along right in here. We hab um. Dere big lagoon way along a little furder."
Thus it proved when the party had forced the boat past the obstruction guarding the river exit. Jim pushed his lever over a very little, and sent his propeller whirling just for so long as would give the launch way against the sluggish stream. As he did so Tom leaned his ponderous figure over the stem, causing it to dip violently, and, gripping the tree, directed the boat into clear water. A few more revolutions sent the launch through, and in time brought her abreast of Sam. They found the little fellow poised on a branch overhanging the water, for all the world as if he were a monkey, and from that position he dropped like a cat on to the deck of the launch.
"What's this about a lagoon?" asked the Major eagerly. "You couldn't see it, surely?"
Sam made no answer for the moment. He took the officer's hand and led him right forward. Then, while Tom clung to a branch to steady the vessel, his smaller comrade bade the Major lie on the deck.
"Not see um if stand up," he explained. "Dem leaves and branches in de way; but Sam see um when he swim. Easy as talkin'. Dere's a young moon to-night, and now that we's right under de trees it's easy 'nough to look out into de open. Dere: ain't dat a lagoon? Gee! Ef I don't tink so!"