Never will the two boys forget that first trip up the big, turbid South American river. From start to finish it was one never ending succession of surprises, interests, wonders and delight. The miles of mangrove swamps, with their aerial roots drooping from the branches into the water, lured the boys’ imaginations with their mysterious, dark depths. A great flock of scarlet ibis, that rose from their feeding ground upon a mud flat and, lighting on the trees, looked like gorgeous fiery blossoms, brought cries of delight from the boys. They watched the big greenheart rafts floating silently downstream with their Indian crews lolling in hammocks beneath the thatched shelters on the logs. Mr. Thorne pointed out dozing alligators which Tom and Frank had mistaken for logs; he showed them the giant, lily-like water plants which he said were “mucka mucka,” and he called their attention to countless bright-plumaged birds which flitted in the foliage of the riverside trees. At times the steamer swung in so close to shore that the boys caught glimpses of frightened, scurrying iguanas or great lizards; at other times, it slowed down and stopped before some tiny thatched hut at the edge of a clearing and unloaded merchandise or people into the huge dugout canoes that put off from shore pulled by bronze-skinned, half-naked men.

“Are they Indians?” asked Tom, as they watched the fellows handling the heavy barrels and boxes with ease.

“No, Bovianders,” replied Mr. Thorne, “a mixture of Dutch, negro and Indian blood. They’re the best boatmen in the colony. I always have a Boviander captain for my boat.”

“What does Boviander mean?” asked Frank. “Is it an Indian name?”

“It has a curious origin,” the explorer informed him. “It’s a corruption of ‘above yonder.’ In the old days, any one who lived up the river from the coast was said to live ‘above yonder’ and gradually the expression was transformed to ‘Boviander.’”

“Well, that is funny!” declared Tom. “I never would have guessed it.”

“You’ll find a lot of queer expressions here,” laughed the explorer. “You’ll hear the people speak of ‘taking a walk’ when they mean a trip in a canoe and you’ll hear them say ‘topside’ when they mean some place which is indefinite. They also speak of the turns of a stream as ‘streets’ and they all use the native Indian names for birds, animals, and trees. They never say ‘tapir’ but ‘maipuri,’ a boa or anaconda is a ‘camudi,’ a camp is always a ‘logi’ or ‘benab,’ a canoe is a ‘coorial’ and so on.”

“Gosh, I don’t believe I’ll ever understand them!” declared Tom, “but I’m going to try. Can’t you get one of your Indians to talk? I’d love to hear that ‘talky-talky’ lingo you spoke about.”

Mr. Thorne laughed. “All right,” he assented and, approaching the edge of the upper deck where the first-class passengers were quartered, he leaned over and beckoned to one of the Indian boys who was dozing in a cotton hammock he had swung in the shade.

“Hey, Joseph!” he called. “Makeum for come here, this side.”

The Akawoia grinned, stretched himself, and came padding on bare feet up the ladder.

“This fellow Buck name Joseph!” said Mr. Thorne, as the two boys looked at the pleasant-faced Indian whose head scarcely reached Tom’s shoulder. “He one plenty good boy. Makeum for tellum white boy how can speakum talky-talky, Joseph.”

Joseph half turned his head and, fixing his eyes on the deck, twiddled his toes in an embarrassed manner.

“No makeum for shame!” went on the explorer. “This fellows white boys makeum plenty long walk topside ’long we. Him wantum sabby plenty--wantum sabby Buck talk, wantum sabby bush, how can makeum for hunt, how catchum fish. Must for tellum, Joseph, must for makeum good fren’.”

The Indian grinned and looked up. “Me tellum, Chief,” he replied in a soft, low voice. “Me be plenty good fren’ lon’side him. How you call-urn?”

“This fellow makeum call Tom,” replied Mr. Thorne, introducing the boys, “Nex’ fren’ makeum call Frank.”

Joseph shook hands gravely with the boys and smiled in a friendly way.

“S’pose you want makeum one walk. S’pose no sabby bush me tellum like so,” he remarked, and then, evidently thinking there was nothing more to be said, he turned and walked silently away.

“Why, that’s easy!” cried Frank as the Indian left. “I’ll bet I can talk that now. You no sabby Tom, me tellum you all same Joseph. How you likeum talky-talky like so?”

“Splendid!” cried Mr. Thorne, and all three roared with laughter at Frank’s first attempt at talking the Indian jargon.

The banks of the stream had now changed from the low mangrove swamps to bluffs and hills of sand; the dense tangle of weeds, mucka-mucka and vines had given place to lofty trees. There were heavy forests stretching away into the distance; tiny clearings and cultivated land showed here and there and the boys caught glimpses of numerous, open-sided, thatched huts among the trees. From time to time flocks of parrots flew swiftly overhead, screeching loudly as they winged their way across the river; herons, blue, gray and white, flapped up at the steamer’s approach. In backwaters covered with gigantic lily leaves the boys saw tiny brown and yellow birds running about, apparently treading on the water, and these Mr. Thorne told them were jacanas, whose long toes enabled them to walk upon the leaves of water plants without sinking.

Then the current of the river became swifter, the steamer chugged and struggled and panted and Mr. Thorne explained that the tide had turned.

“You don’t mean to say that they have a tide clear up here!” exclaimed Tom in surprise.

“For nearly one hundred miles up the rivers,” the explorer assured him. “Of course, the salt water doesn’t come up here, but the tide backs up the rivers so there is a rise and fall of nearly six feet up to the first rapids or cataracts as they are called.”

“Jimminy, are there rapids?” asked Frank.

“Rapids!” ejaculated Mr. Thorne. “Why, my boy, there are nothing but rapids. It’s just one rapid and fall after another.”

“Hurrah, that will be great!” declared Frank. “I’ve always wanted to run rapids.”

“You’ll run enough to last you for life,” Mr. Thorne assured him. “And you’ll have enough of them and to spare. It’s all right running them when you’re coming downstream, but it’s slow, heartbreaking work going up. Why, it often takes days to haul up a rapid that we shoot in less than an hour coming down.”

“I see where I’d like to have that blamed old plane,” exclaimed Rawlins, who had arrived in time to hear the explorer’s remarks. “If they see us coming, there won’t be much chance of catching them. A plane’s the thing for this country.”

“Leave that to the Indians,” chuckled Mr. Thorne, “When we locate the plane the rest will be easy--that is, if we can overcome the Bucks’ superstitions enough to get them to touch the plane.”

“By glory, that’s a good idea!” declared the diver. “If they see Indians they won’t be suspicious and they’ll never know we’re near until we march in and say ‘hands up.’”

“They won’t see the Indians,” said Mr. Thorne decisively. “You don’t know the Guiana red man, Mr. Rawlins. A shadow is a noisy and tangible thing compared with him.”

“Oh, look, there’s a ship!” cried Tom, pointing ahead to where the masts of a large vessel showed above the trees.

“Yes, she’s off Wisniar--loading greenheart, I expect,” assented the explorer. “We’re almost at the end of our steamer trip.”

“But how did a big ship get up here?” inquired Frank.

“Ocean liners can come up here,” replied Mr. Thorne. “The river is deep and it’s not unusual to see several big tramps up here loading greenheart or even farther up at Akyma loading bauxite--aluminum ore, that is. An American company is developing a large mine there.”

“Oh, there’s the town!” cried Tom.

A few moments later, the steamer was being moored to a rickety wharf before the little settlement and the boys were surprised to see a diminutive locomotive and a train of toylike cars standing on a track near the landing.

“Why, they have a railway here!” exclaimed Prank. “Pshaw! this isn’t wild a bit.”

“It’s the jumping-off place of civilization,” said Mr. Thorne. “The railway merely runs across to Rockstone, a settlement on the Essequibo River.”

Rapidly the motley crowd of passengers disembarked, Mr. Thome’s two Indians, reËnforced by five others who appeared to spring by magic from nowhere, shouldered the party’s baggage, and Mr. Thorne led the way to a large dug-out canoe which was moored near the dock.

“We’ll spend the night across the river,” he explained, as the Indians piled their loads in the “coorial” and the boys and their companions seated themselves. “There is a hotel here,” he continued, “but it’s a rotten hole and my Boviander captain has a nice place where we can be far more comfortable.”

Pushing off from shore, the Indians grasped their paddles and with swift, powerful strokes drove the craft diagonally across the river, swung it deftly into a small creek, and ran its bow on to a mud bank from which a notched log led up to the higher land.

Standing at the head of the improvised steps was a powerfully built, yellow man with grizzled curly hair, a heavy mustache and a pair of keen gray eyes.

“Howdy!” he greeted them with a pleasant smile, “I’se please to see you retarn, Chief.”

Mr. Thorne shook his hand warmly. “Glad you were here, Colcord,” he exclaimed. “These are the gentlemen and the boys that are going up river with me.” Then, turning to the others, “This is Captain Colcord, my boat captain,” he announced. “And there’s none better in the colony.”

The Boviander flushed under his dark skin and then, shaking hands with each member of the party in turn, led the way along a narrow path between the trees.

“You’ll have to tell Colcord something of our plans,” said Mr. Thorne, speaking to Mr. Pauling in subdued tones. “He’s perfectly dependable and can keep a secret, but we can’t accomplish much unless he knows what we want to do.”

“Very well,” assented the other. “I trust to your judgment, Thorne.”

Colcord’s house proved a revelation to the boys. It was merely a huge open shed, with a high, thatched roof, a floor of hewn boards raised several feet above the earth, and one small room partitioned off by wattled palm leaves. Its furnishings consisted of a rough table of native wood, a few cheap chairs, a number of big hammocks, a nickel-plated alarm clock, and an American lantern. On the rafters overhead were spread woven palm leaf mats on which were placed Indian baskets and trays; a huge red earthen jug of water stood on a tripod of hard wood sticks; a long, highly polished bow and several six-foot arrows were laid upon a timber; and a single-barreled gun stood in a corner. It seemed scarcely more than a camp and might well have been the home of an Indian, but they soon found that this rude and primitive dwelling was very comfortable and that, despite its simplicity and its meager furnishings, no necessity was lacking.

Colcord’s wife, who appeared to be of nearly pure Indian blood, was busy over a tiny fire in a small shed in the rear and no sooner had the Indian boatmen brought the baggage into the house than they joined her and seemed perfectly at home. Presently the Akawoia, Joseph, appeared, carrying a steaming earthenware pot, and Colcord rapidly produced dishes and cutlery and set the table. As he moved about and Joseph brought in more steaming dishes, the boys lolled in the hammocks in the deliciously cool breeze and idly watched the chickens, doves, and woefully thin dogs that swarmed about the house. They knew that less than a mile distant was a town, with railway trains, a sawmill, and shipping, and that only a few hours’ travel by steamer was the big busy port of Georgetown, and yet, they could not help feeling that they were in the heart of the jungle and far beyond the reach of civilization.

“Gosh, isn’t it great!” exclaimed Tom. “This is really camping out.”

“You bet!” replied Frank. “I wonder if there are any wild animals about.”

“Plenty deer,” declared Colcord, who overheard Frank. “I made fo’ to kill one this marnin’. I ’spect you folks plenty hungry, no?”

“Well, I have got a mighty good appetite,” admitted Tom.

“Me too,” added Frank. “Gee, that food smells good!”

“O. K., then,” declared the Boviander. “Jus’ draw up an’ he’p yourselves. I ’spect you’re not accustom’ to rough livin’ like this, an I have to ’pologize fo’ not havin’ more better.”

“Now don’t say a word!” Mr. Thorne admonished him, as the party drew chairs to the table. “I’ll bet they never tasted anything better than this venison and yams and pepper pot, and it’s like the Ritz compared to what we’ll be getting from now on.”

Every one declared that Mr. Thorne was right and that they had never tasted anything to equal the roast venison, the boiled yams, the fried plantains and the pepper pot.

The boys were particularly enthusiastic over the last and also over the crisp, toasted cassava bread and were greatly surprised to learn that both were made from the deadly poisonous bitter cassava root.

“The juice is the poisonous part,” explained Mr. Thorne. “After it’s squeezed out through a cylindrical sieve called a ‘metapee’--that’s one hanging over in the corner--any traces of the poison, which is prussic acid, are driven off by baking the meal into these cakes. The poisonous juice boiled down makes the pepper pot. It has the property of preserving meat and giving it this delicious flavor. It’s really the national dish of Guiana.”

“Well, it’s good enough to be the national dish of any country,” declared Rawlins. “Just fill my plate up again, Mr. Thorne.”

The meal over, the party made themselves comfortable in the hammocks and, as pipes were lighted, the explorer told Colcord that they were going in search of an aircraft which had last been sighted flying to the south over Wismar.

“It’s of the utmost importance that we find it,” he said. “The men in it are desperate criminals and Mr. Pauling and Mr. Henderson are officials sent out by the United States Government to get them. They want those men dead or alive--alive preferably--and we expect you to help us. We have no idea where the machine is, but we have an idea they are hiding somewhere not far away. Now do you suppose we can trail that plane and get the men, Colcord?”

“Yes, Sir--Chief,” replied the Boviander confidently. “But we’ll never fin’ it over this side, Chief. That airship’s went up the Essequibo topside. I was makin’ a walk up beyon’ Malali for locus’ gum an’ I never cotch a glimmer of it, but ol’ Charlie--the Macusi what lives over Mule Pen side, you know--he was huntin’ pacu on the Tukumi Creek an’ he mek to get mos’ frighted to death when she fly over. Yes, Chief, I sure we make our walk up the Essequibo top side we boun’ for to find she.”

“Hmm, very likely,” agreed the explorer. “Can we get a boat at Rockstone?”

“I can’ say rightly, Chief,” replied Colcord. “But I ’spect you can. Le’s see, they’s seven of you, an’ we’ll need a plenty good size boat an’ ’bout ten men an’ bowman asides me. You got Joseph, an’ Billy an’ Bagot an’ Carlos an’ Theophilus an’ Abr’ham. That’s six, an’ I reckon I can s’cure free more boys an’ Boters for bowman, but I can’ rightly say ’bout the nex’ man.”

“Ah can paddle,” put in Sam who had been very silent. “Ah don’ lay to do narthin’.”

The Bovinander glanced approvingly at the Bahaman’s powerful arms and shoulders. “Yes, son, I ’spect you can,” he agreed. “You surely is a strong-lookin’ boy.”

Everything was soon arranged, one of the Indians was sent off to notify the men Colcord had in view, and, in preparation for an early start the next morning, all turned in almost as soon as it was dark.

The boys had never before slept in hammocks and, although Mr. Thorne and Colcord showed them how to wrap themselves in their blankets and lie diagonally across the hammocks, it was some time before they could make themselves comfortable and go to sleep. It was a new sensation to be thus going to bed practically in the open air and for a long time the boys remained awake, listening to the multitude of strange and unusual sounds which issued from every side. There were chirps, whistles, squeaks, and strident songs of insects; thousands of frogs croaked and barked and grunted; night birds called plaintively; owls hooted and from the forest in the distance came a roaring, reverberating bellow which Tom was sure must be a jaguar. But Mr. Thorne laughed and assured him it was merely a troop of howling monkeys or baboons and, to put the boys more at ease, he patiently identified each of the unusual noises that disturbed them. Gradually, realizing that there was nothing more dangerous than frogs or monkeys to be feared, and assured by the explorer that even the vampire bats would keep away as long as the lantern was kept burning, the two boys quieted down and, watching the myriad giant fireflies, dropped off to sleep.

It seemed as if they had scarcely closed their eyes when Colcord’s cheery cry of “Fireside” aroused them and they sat up, yawning sleepily, to find the sky across the river pink and gold with the coming dawn.

It was cold and chilly and the steaming coffee which Colcord had ready was very welcome.

“Golly, I thought the tropics were hot!” exclaimed Frank, as he beat his arms about and tried to keep his teeth from chattering.

Mr. Thorne chuckled. “Not at night--in the bush,” he replied. “You’ll find colder nights than this after we get farther up river.”

“Whew! I’ll want an overcoat then,” declared Tom, “or a furnace fire!”

But the boys’ chill was only temporary and a little exercise, combined with piping hot food, soon made them forget all about the cold morning air and by the time they were ready to embark in the canoe and cross the river the air was balmy and springlike.

The boys found little of interest on their ride across from Wismar to Rockstone by the railway, for the train passed through land which had been stripped of its forests by the lumbermen and the few remaining trees stood gaunt and dead above a tangle of weeds and shrubs. But at Rockstone they were delighted, for, close to the station, flowed the great Essequibo River, dark and mysterious, with its shores covered by the impenetrable tropic jungle. To them this mile-wide, silently flowing stream gave an impression of the unknown and savored of adventures to come, for Mr. Thorne had told them that its source was near the borders of Brazil and that much of its rapid and cataract-filled course led through country never seen or penetrated by white men.

The boat was ready and waiting, for the Indian sent by Colcord had made his way across to Rockstone and had arranged everything, and already the additional members of the crew and the bowman were stowing the outfit in the craft.

Within half an hour of their arrival the boys and their friends were seated under the arched canvas awning or “tent” near the stem, the nine Indian paddlers, with Sam, were in their places, and the bowman, grasping a huge paddle, was perched precariously on the boat’s prow. Colcord stepped on to the stern and slipped an enormous paddle through a bight of rope. Then, to his shout of “Way-ee-oo!” the ten paddles dug into the water as one, the heavy, spoon-bottomed boat sprang forward, and Colcord straining at his great steering paddle, headed the speeding craft upstream. Five minutes later Rockstone with its houses, its railway station and its docks, slipped from sight behind a wooded point and only the sullen, mighty river and the endless jungle stretched ahead.