It was easier said than done. The overnight conflagration had destroyed every vestige of brushwood. With the prospect of being leapt upon by a highly formidable jaguar or seized by a boa-constrictor already incensed by the proximity of a high-velocity bullet, it was not advisable to attempt to gather driftwood under the base of the low cliff. To attempt to fish pieces of floating brushwood from the river, when in the dim light it was a matter of impossibility to distinguish between a waterlogged tendril and a watersnake—and at the same time to present their backs to the lurking foe on the rocks—was also too risky a proposition.
"We'll have to sacrifice some of our petrol," decided Uncle Brian. "There's some cotton waste in the locker under the fore-deck."
The waste soaked in petrol was placed on the ground at a safe distance from the boat. A match was applied and the flames shot high in the air, accompanied by a hissing sound that could not be attributed to the combustion of the highly volatile spirit.
At intervals Peter replenished the fuel by the simple expedient of squirting petrol from a syringe. The flames were brilliant enough, but still the spluttering noise continued.
Thus the two men spent the weary and anxious hours until the time should come when there would be enough light to enable them to continue their voyage, the while keeping eyes strained and ears alert for indications of danger.
Suddenly the air was rent by a terrific shriek ending in a long-drawn-out howl. Somewhere beyond the edge of the low cliff a heavy body was thudding violently against the hard ground.
Then for a few seconds, exposed to the full glare of the petrol flare, appeared the head and fore-quarters of the jaguar. The animal's eyes were almost starting from its head; its mouth was wide open, displaying a double row of glistening teeth and a red, lolling tongue.
Peter raised his rifle, but before he could press the trigger, the head and shoulders disappeared. A brief interval ensued, then the jaguar's hind-quarters appeared, the clawed feet pawing aimlessly in the air.
"Don't fire!" shouted Uncle Brian. "He's got more than he bargained for. The anaconda's seized him."
The rest of the tragedy was hidden from human view, although the sounds from the scene of anguish gave a pretty clear indication of what was taking place. Held in the remorseless tension of several coils,the jaguar was being slowly crushed to death. Nevertheless, it was putting up a strenuous resistance, rolling over and over in a vain attempt to crush the anaconda by the weight of its body. Gasps and howls of agony rent the night air which, already heavy with pestilential odours, now reeked of blood and the nauseating smell from the huge reptile.
The cracking of the jaguar's ribs under the irresistible pressure was now distinctly audible. The groans ceased. The anaconda was preparing for its gargantuan meal.
"Can't we make a move?" asked Peter. "This stench is simply unbearable."
He would have willingly risked the hidden dangers of that uncharted, cayman-infested river in the darkness to get away from the noxious camping-place, but Uncle Brian was obdurate.
"We must stick it till dawn," he declared firmly, but without giving any reason.
At length the day broke with the rapidity common in the Tropics. The roaring of the beasts of the forest died away and a strange stillness brooded over the now languid river.
"Thank Heaven!" ejaculated Peter fervently. "Now for a fresh start."
"We'll have a look at our friend the anaconda," suggested Uncle Brian. "The reptile did us a good turn, I fancy, for the jaguar was on the point of springing at us when he was seized."
There was little need for caution. On climbing upthe rocky ledge they found the anaconda still engaged in swallowing its prodigious meal. The reptile was about twenty-five feet in length and normally as big round as a man's thigh, but now it was tremendously distended in spite of the fact that the head and half of the body of the jaguar, crushed almost to a pulp, had yet to be consumed.
It was not a sight to watch for long. The men returned to the boat. Then Uncle Brian unburdened himself.
"Don Ramon and his pals evidently don't want us to return to El Toro," he said abruptly.
"I'm not altogether surprised at that," rejoined Peter. "But where are your proofs, Uncle?"
"Here," replied Brian, indicating his double-barrelled gun and the petrol tins. "This gun has been tampered with. The striking mechanism has been thrown out of action. That's why you had two missfires. And the petrol has been liberally watered; I guessed as much when it spluttered. Before we get under way, we must pass every drop of petrol through a strainer."
The gun was beyond repair with the limited tools at their disposal. For all useful purposes the weapon and a hundred shot-cartridges were so much lumber. They had better luck with the "doctored" petrol. By means of a strainer and a piece of fine muslin, the spirit was practically freed from water. In the process the fuel supply was appreciably diminished, for every tin had been tampered with, except the one whichhad supplied the petrol for the previous day's run.
The double discovery was a disconcerting one. Nevertheless, it left Brian Strong a tolerably free hand. The mask was off. Either Don Ramon Diaz had his suspicions, or else he had no longer any need for the Englishman's services, and in that case had no scruples about descending to a trick by which Brian and Peter might meet with disaster and death in the wilds of the Upper Rio Guaya, or its tributary the Rio Tinto.
It was half-past eight in the morning before the voyage was resumed. Before long, the confluence of the Rio Tinto and the Rio del Morte was sighted. Brian, who was steering, ported helm and shaped a course towards the left bank, where the latter tributary joined its coffee-coloured waters with those of the Rio Guaya.
Presently Peter, who was engaged in cleaning out the barrel of his Express rifle, happened to glance skywards. Following the boat at a height of about two thousand feet was one of the units of the Rioguayan air fleet.
How long the flying-boat had had them under observation, neither Peter nor his uncle could say. The rapid throb of the outboard motor had prevented them hearing the deeper roar of the flying-boat's quadruple engines.
Knowing to an almost absolute certainty that the aircraft's crew had them under clear observation by means of powerful binoculars, Uncle Brian carefully avoided looking up. A sudden alteration of helmwould be a false move. He kept steadily in his course for a few minutes before putting the helm to starboard and making for the Rio Tinto.
"That's awkward," remarked Uncle Brian. "They won't leave us alone. We'll have to make a feint of ascending the Rio Tinto. It will mean a day's delay and a night dash for the Rio del Morte."
"Perhaps when they see we're well on our way up the Rio Tinto they'll clear off," hazarded Peter.
Apparently his surmise was correct, for after circling overhead for three hours, the flying-boat disappeared in the direction of Tepecicoa, without having made any attempt to molest or even communicate with the Englishmen.
During the heat of the day the fugitives rested, anchoring their little craft by means of a big stone and a rope in the shade of an overhanging tree. Here they were screened from aerial observation, but no buzz of propellers disturbed their rest. The flying-boat had, in fact, returned to the base with the news that the mad Englishmen had really taken the Rio Tinto course.
It was not until four in the afternoon that the outboard motor was restarted and the course retraced to the Rio Guaya. Not without considerable trepidation, Brian steered across the broad river and made the narrow entrance to the sinister Rio del Morte.
Here the banks were lofty and precipitous, the stream flowing at the rate of four miles an hour through a bottle-necked gorge of less than a hundred yards in width and nearly a mile in length.
Progress was in consequence tediously slow, an hour elapsing before the boat joined the wider expanse above the defile. Ahead the river broadened still more into a fairly large lake which the map had entirely ignored. At the farthermost end the flat shores were broken by a number of rocky pinnacles, but whether they were small islands or merely parts of the mainland, it was as yet impossible to determine. The forests had now been left behind, the shores of the lake being treeless and bare, save for occasional patches of pampas grass and cacti.
"Think we'll fetch the other end before dark, Uncle?" asked Peter. "It's quite five miles off."
"Might," replied Brian unconcernedly. "It doesn't matter much if we don't. We're carrying on at night. I think we decided upon that?"
"Yes," agreed his nephew, "we did. But we didn't reckon on having to navigate a lake. We don't know where the inlet is. It might be between any of those projections we can see ahead; and it will be no joke barging about on a dark night trying to find a way out."
"We'll do it, never you fear," rejoined his uncle, with one of those bursts of sublime optimism that characterized his mercurial spirits.
Soon it became evident that Peter had miscalculated the length of the lake. Darkness was drawing nigh and still the range of rocky pinnacles was far enough away to baffle any attempt to fix the channel with any degree of reliability.
The wind, too, hitherto light, was piping up deadastern and against the slight but distinctly perceptible current.
Peter was steering. More than once he glanced astern at the curling waves. In a craft possessing any degree of seaworthiness he would not have troubled to look behind him, knowing the short-crested waves would pass harmlessly under the boat's keel. But the keelless type of freak construction was already giving signs of trouble. The metal rudder, of absurdly insignificant proportions, had little or no grip, except when at short intervals the narrow stern, weighted by the heavy outboard engine, dipped dangerously in the hollow water. At one moment the engine was almost stopped by the increased resistance of the deeply immersed blades; at another, the motor was racing furiously as the "orange-box" buried her bows and threatened to broach-to.
Both men realized the danger. Wave-crests were flicking over the sides of the little craft. Brian Strong was busily engaged in baling. Peter was endeavouring to keep the boat on her course, the while striving to discern an outlet between the still distant rocks.
Presently darkness fell upon the scene. The wind was increasing and now blew with the force of a "fresh breeze". Peter would have laughed at it in a seaworthy centre-board dinghy, but in present conditions, he knew it was far from being a laughing matter. Somewhere, and not very far distant by this time, was a lee shore. The "rebound" from the land at this end of the lake was already becoming apparent, for thewaves were now becoming irregular and confused. Uncle Brian's task was a difficult one, for of all sorts of craft those with flat bottoms are the most awkward to bale out. In spite of his strenuous efforts the water was gaining. He communicated the news to his nephew.
"All right!" shouted Peter encouragingly. "I'll round to. Pass an oar through one of the sleeping-bags and weight the lower end of the bag. It will make a sea-anchor and we can ride to that. Call out when you're ready."
Uncle Brian understood. Although not a seaman, he was used to small boat work. He began to prepare the sea-anchor, which when hove overboard would keep the boat's head to wind, act as a floating breakwater, and reduce her drift to a little less than a mile an hour.
Suddenly the boat's stern dipped more than before. A wave broke inboard, sweeping completely over the outboard motor. The engine stopped. Either the water had short-circuited the high-tension wire, or else had found its way into the carburettor.
Immediately, the "orange-box" swung round broadside on to the wind, with the water already up to her crew's knees.
"Be sharp!" cautioned Peter, at the same time grasping a can of lubricating oil, unscrewing the cap, and throwing a quantity of the heavy liquid to wind'ard.
The action of the oil immediately quelled the waves, the boat drifting to lee'ard of a wide and steadilyincreasing patch of smooth water. But so rapid was her drift that she quickly drove beyond the oil-quelled area, and once more the waves swept over her side. Again Peter attempted to pour oil upon the troubled waters, but the can slipped from his grasp and disappeared overboard.
A moment later, the flat-bottomed craft heeled, recovered herself sluggishly, and slid beneath the waves.
The shock of being immersed feet foremost in the water, coupled with the fact that the night was pitch-black, was quickly followed by a quite unexpected discovery.
The boat had foundered, but a heavy jar proclaimed the fact that she had "struck soundings" in about three feet of water. Her crew found themselves standing waist-deep upon the quivering boat as the bottom boards writhed under their feet in an attempt to float to the surface—a feat that had been successfully performed by most of the buoyant gear in the boat.
For some moments neither Peter nor his uncle could grasp the situation, until Brian Strong shouted: "We're close to shore; come on, Peter."
"Don't move!" bawled Peter, for conversation at an ordinary pitch would be inaudible owing to the shriek of the wind. "Don't move. We may be on a sandbank with deep water all around."
Uncle Brian saw the force of this assertion. It would be a fool's trick to attempt to swim, since all sense of direction was lost, and they were still ignorantof how far it was to the nearest land. Visions of caymans, deadly eels, and other undesirable denizens of these waters also served as a deterrent, although, standing waist-deep, the two men were not less liable to attack than had they been striking out for the shore.
"I'm not at all keen on standing here till daybreak," remarked Uncle Brian at length. "It's too jolly moist," he added, with a brave attempt at making light of the situation.
"I'll tell you what I'll do," decided Peter. "There's a coil of rope under the fore-deck. Pass it aft and I'll secure one end round my waist. Then I'll go on a voyage of exploration. If the water gets deeper I'll come back. If it shelves, we'll move along till we find a better 'ole."
"Better hump, you mean," corrected Brian Strong. "All right, here's the line. I'll pay out as you go. There ought to be thirty fathoms of it at least."
Having made his preparations, Peter stepped off. The ground was quite hard under his feet and clear of weeds. Nevertheless, he proceeded cautiously, having in mind the possibility of encountering a cayman or other ferocious inhabitant of the lake.
He had his automatic, but he was doubtful whether it would be serviceable. The cartridge in the barrel might be effective, since the ammunition was guaranteed damp-proof; but there was the chance of the delicate mechanism of the weapon being deranged by its submersion. Nor was an automatic of much use against a cayman. The bullet was not powerfulenough to penetrate the creature's armour-plated body; and unless a lucky hit were made in the cayman's eye or throat, the odds would be against Peter. All the same, the possession of the automatic gave him a certain degree of confidence that would have been lacking had he been weaponless.
He had traversed about twenty yards when he encountered a dark object that well-nigh capsized him. Visions of an electric eel flashed across his mind. For a moment he floundered panic-stricken, striving to break away from the object that was clinging tenaciously to one foot.
Then the real nature of the thing became apparent. It was the sleeping-bag that Uncle Brian was preparing as a sea-anchor when the boat sank.
Disengaging the short oar from the bag and using it as a sounding-pole, Peter resumed his semi-aquatic walk.
If anything, the water was shoaling. Once or twice it was almost up to his shoulders, but mostly it was only knee-deep and the bottom level. For another thirty yards he progressed, and then looming through the darkness he could discern the irregular outlines of a rocky coast at a distance of about fifty yards.
That was good enough. Retracing his steps, a feat only rendered possible by the aid of the rope, Peter communicated the result of his discoveries to Uncle Brian.
During the last half-hour the wind had veered,with the result that the waves had died down completely—another indication that the lee shore had obligingly become a weather one.
"How about our gear?" inquired Uncle Brian.
"What has floated is most likely ashore by this time," replied Peter. "The heavy stuff can stop in the boat till daybreak. We'll make fast the rope and take the other end with us. That will help us to find the boat later on."
This suggestion was acted upon, but when Uncle Brian stepped out of the boat to join Peter in their walk to the land, the bows, relieved of his weight, appeared above the surface.
"I say!" exclaimed Peter. "She's almost waterborne. It's only the weight of the engine that's keeping her stern down. We can drag her with us."
Each man grasped one gunwale. The "orange-box"—that, but for the shallowness of the water, might have been a coffin—was moved shorewards with comparative ease, until the gunwales were awash and the bottom aground. Exerting all their strength, the two men found it impossible to move her another foot.
"We're here, anyway," declared Uncle Brian, regarding the rocky shore with feelings of thankfulness.
"We are," agreed Peter grimly.
"And marooned on an island most likely," added his relative. "S'pose there's nothing for it but to wait till day."
"To work," corrected Peter. "We must get thegear out of the boat. The rifle will want drying pretty quickly if it's to be of any use. And the engine too." They set to with a will. The outboard motor was unclamped and carried ashore, together with the precious parts of the secret-rays apparatus, the bedding, and provisions. Several articles that had drifted ashore were also found and placed in a position of comparative security.
"Now we can get the boat up a bit higher," declared Peter. "If we can't find the baler we may be able to cant her over and get rid of the water."
With a lusty "heave-ho!" the waterlogged boat was dragged her own length nearer the shore, but all attempts to turn her on her side were unavailing. So they contented themselves by making the boat fast and leaving her till dawn.
It was a long, dreary vigil. They were without means of making fire, since their stock of matches was spoilt by the water. Bully beef and sodden biscuits provided a sorry meal, and the rest of the night was spent in constantly keeping on the move in order to mitigate the discomfort of wearing saturated clothing.
By way of contrast to their previous night's camping-ground, the place was strangely quiet. No roaring of wild animals or splashing of caymans disturbed the solitude. The wind had died entirely away and not even a rustle came from the scanty clump of trees, showing dimly above the brink of the precipitous rock. At last, to the tired eyes of the weary men appeared a pale pink glow in the eastern sky. Five minutes laterit was quite light, and the comforting beams of the rising sun were glinting over a distant range of hills.
Peter and his uncle were now able to take stock of their surroundings. The gravel beach was piled with their water-logged belongings. A little distance away was the boat with her nose and one gunwale showing; beyond, the now tranquil lake with the furthermost shore hidden in a fleecy mist.
They had come ashore in a sort of shallow bay bounded by bluffs of iron-grey rocks and connected by an irregular wall of granite-like stone, averaging fifty feet in height.
"The sun will soon dry our gear," said Peter. "We can make a fire by means of one of the lenses of our binoculars. Suppose we climb up to the top of the cliff and see where we are?"
"You can," replied Uncle Brian. "I'm as stiff as anything. I'll stop here and start a fire. Don't forget to take your rifle."
The rifle had already been cleaned as far as Peter was able to do so; and for lack of suitable oil he had washed out the barrel, magazine, and mechanism with petrol.
It was a fairly easy ascent, for the cliff face was covered with horizontal clefts that afforded a secure hold. Nor was the cliff so steep as it had looked to be in the darkness.
Peter was but little wiser than before when he reached the summit. The higher ground farther inland prevented any extensive outlook in that direction;but beyond the projecting bluffs that bounded the bay the lake was visible on either side. The land upon which they had been cast was either a wide peninsula or else an island.
Anxious to settle the question, Peter made his way towards the highest peak, which was about three-quarters of a mile away. It was easy going, for, with the exception of a few clumps of trees and patches of thorns, the ground was bare and sunbaked. For the most part it consisted of lava-like rock mingled with veins of granite, but here and there were patches of hard mud intersected by fissures of considerable depth.
The only signs of animal life that Peter saw were a few vividly-coloured lizards and an animal strongly resembling a hare; and although he kept a sharp lookout for snakes basking in the now powerful rays of the sun, none appeared, much to his satisfaction.
When Peter returned to the beach, he found his uncle busily engaged in making tea. A fire was blazing strongly, and from a tripod composed of the oars and boat-hook a "billy" hung over the flames.
"It's a jolly good thing we've still got the boat, Uncle," said his nephew. "I've been to the highest ground about here and we're on an island."
"Just our luck," rejoined Uncle Brian. "The boat's got a hole in her as big as my head. But we can discuss that later. Breakfast first."
Without the shadow of a doubt, Uncle Brian had risen to the occasion. The biscuits were little the worse for their immersion and, when flavoured withtinned pilchards and bottled tomato soup, were eaten with gusto. The tea, having been stored in an airtight case, was in splendid condition, although Peter deplored the fact that there was no sugar available, and that the condensed milk was of the unsweetened brand.
The meal over, the two men settled down to serious business. An examination of the boat confirmed Uncle Brian's statement. Right amidships was a fairly clean hole about fifteen inches in diameter. A blanket had, by some means, got underneath the bottom boards and had become wedged in the hole, with the result that when the two men had attempted to drag the boat clear of the water, the fabric prevented a free outlet. Now that the obstruction was removed, it was a comparatively simple matter to drag the damaged craft well up on the beach.
"That's one advantage of not having a keel," said Uncle Brian. "We can patch the hole from the outside."
"We can," replied Peter, "but——"
"But what?"
"Now that there is a gap amidships why not use it to take the propeller?" suggested Peter. "It would make the old coffin a jolly sight more seaworthy with that weight transferred from over the stern to the 'midship section."
Brian Strong regarded his nephew suspiciously. He was wondering whether Peter was wandering in his mind, or trying to "pull his leg".
"I mean it," continued Peter.
"Well, what's to keep the water out?"
"This," replied his nephew, indicating a zinc-lined wooden box in which the provisions had been stored. "Knock out the bottom and secure the four sides to the bottom of the boat like a square centre-board case. We'll have to caulk the joints and stiffen the box with cross bearers to take the strain of the engine."
"Good idea, that," agreed Uncle Brian. "I shouldn't wonder if we get another one and a half knots out of her. She won't drag her stern down so much."
"That'll be something to be thankful for," declared Peter. "That stern of hers is a positive danger. Let's set to work."
On taking stock of the tools at their disposal, they found they possessed a hatchet, screw-driver, hammer, mallet, and gimlet. There were also copper nails and a few brass screws.
By about eleven (judging by the sun, for their watches had been stopped by water penetrating the cases) the box was in position, being secured by two-inch screws through the bottom of the boat. For caulking they used unlaid rope soaked in oil, and clay thinned down with grease. Strips of wood from one of the bottom-boards screwed together formed strengthening cross-pieces. Altogether they had made a sound job in a comparatively short time.
"We'll knock off for a bit," said Uncle Brian, wiping the perspiration from his eyes. "It's toorisky to swot in the midday heat. We'll make another start when it's a bit cooler."
"Right-o," agreed Peter, throwing down his tools with alacrity. "If——"
He broke off suddenly and pointed.
Brian Strong looked in the direction indicated by his nephew's outstretched hand. Then he muttered under his breath, for a couple of miles away was the misty outline of a Rioguayan flying-boat.
"Take cover!" exclaimed Peter warningly, at the same time making for his automatic and ammunition, which were lying on one of the blankets spread out on the beach.
"Too late, I fancy," replied Brian. "They've spotted us for a dead cert. We were fools to leave the boat and all this gear strewn over the sand."
Nevertheless, Uncle Brian grasped the rifle and automatic pistol and a haversack containing parts of the secret ray invention. Come what may he was not going to letthatfall into the hands of the Rioguayans.
"Which way?" he inquired.
"Up the cliff," replied Peter. "We may be able to stow ourselves away before they are sufficiently above us. There's not very much cover, worse luck."
It was fortunate that Peter Corbold had previously found a way to the top. Profiting by the experience, uncle and nephew quickly gained the summit of the cliff.
The flying-boat was now about a mile away, but wasshaping a course that would bring her to the west of the island.
"Don't believe they've spotted us yet," declared Peter. "But they are bound to see our boat if they start cruising over the island. Look! What's wrong with that?"
He pointed to a cleft in the face of the cliff about twenty yards to the left of the spot where they had made the ascent. A closer acquaintance showed that the hollow was deep and narrow, descending steeply until it terminated in a natural breastwork about eight feet above the beach. Although open to the air, the enclosing walls of rock were sufficiently irregular to cut off direct observation; and as neither Peter nor his uncle had noticed the cleft from the beach, it being similar to a dozen others, they were fairly safe in assuming that they stood a chance of outwitting their pursuers.
They could hear the drone of the motors, but were unable to see the inquisitive flying-boat. For some minutes the noise continued almost constant in volume, as if the machine were hovering in the vicinity. Then the sound grew louder and louder until it ceased abruptly.
Peter knew what that meant. The Rioguayan airmen had discovered traces of the two Englishmen and were volplaning down to investigate.
Suddenly the descending aircraft appeared within Peter's limited field of vision, since by cautiously peering over the breastwork he could command a viewof the beach in the vicinity of the spot where the two Englishmen had landed.
There was nothing to criticize adversely in the manner in which the flying-boat alighted on the surface. With hardly a splash the lightly-built hull took the water. A few revolutions of the for'ard pair of propellers and the flying-boat "taxied" until she touched the edge of the sandy beach.
If there had been any doubts in the minds of Peter and his uncle as to the intentions of the Rioguayan airmen, there was now no uncertainty on that score.
A couple of men jumped out and secured the gently swaying flying-boat by means of a grapnel and rope. Then several more leapt ashore, all fully armed with rifles, revolvers, andmachetes. Almost their first act was to smash the little craft which the Englishmen had only just succeeded in repairing.
The Rioguayans seemed to take a childish delight in their work of destruction, laughing, yelling, and gesticulating at the thought that they had run their quarry to its lair and had cut off the fugitives' means of escape.
Not content with smashing the boat to firewood, they examined every article that was strewn on the beach, destroying some and passing the rest into the hull of the flying-boat.
Peter glanced at his uncle and tapped his automatic significantly. At all events, he thought, since the Rioguayans had deprived them of a means to leave the barren island, there was no reason why the twoEnglishmen shouldn't open a destructive fire upon their now declared foes. At that short range there was a good chance of killing or wounding every man in the group on the beach.
Uncle Brian shook his head.
"Wait," he whispered.
Peter felt positively mutinous. To remain inactive was to throw away their only chance of scoring heavily off their pursuers.
"Why?" he demanded in a low voice.
"They're going to search for us," was the reply.
Brian Strong had the Rioguayan airmen's own words to support his statement, for amid the babel he managed to overhear one of the men declare that the Englishmen must be found, and taken prisoners. These were the Comandante's explicit instructions.
There were now eight of the crew on the beach, all of them arguing with each other and paying scant heed to the excited shouts of an officer in the pilot's seat of the flying-boat. At length two of the crew went on board, reappearing with a long, scraggy dog, whose chief points were his long drooping ears and lolling tongue. Brian Strong recognized the breed as a cross between a Cuban bloodhound and a Brazilian whippet. The dog was carried ashore in spite of its weight, the apparent reason being that for the purpose for which it was intended it must not walk through water.
At the sight of the hound Brian felt more ill at ease than he had since the appearance of the flying-boat.He knew the ferociousness of the breed and their skill in following the trail of a fugitive. He almost wished he had fallen in with his nephew's unspoken suggestion and had tried the moral and physical effect of a sudden and unexpected burst of automatic pistol firing.
It was too late for that now. The opportunity had passed, for already some of the men were screened by the intervening wall of rock.
So Brian watched the movements of the two men with the dog, noting with considerable apprehension that both fellows, in addition to their firearms, carried a supply of hand-grenades, which might or might not be smoke bombs.
Presently they, too, passed out of the Englishmen's arc of vision; but from auricular evidence, it was plain that they were experiencing considerable difficulty in persuading the animal to scale the cliff. But one point was distressingly in evidence; the hound was already on the trail, since he had indicated the way by which Uncle Brian and Peter had gained the summit.
It seemed quite a long interval before the baying of the hound announced that the feat of the ascent was accomplished. Momentarily the two fugitives expected to hear their pursuers descending the narrow gorge in which they were concealed, but minutes passed without their unpleasant expectation being realized.
Gradually the deep notes of the dog, accompanied by the encouraging shouts of the searchers and the occasional report of firearms, died away.
"Good business," whispered Peter. "The brute's picked up the wrong scent. He's following my track where I went this morning."
Which was exactly what the hound was doing, accompanied by the airmen who were firing at haphazard into every bush they passed, on the chance of compelling their quarry to abandon a possible place of concealment.
Peter took another look at the flying-boat. He could see the officer in charge sitting up in the for'ard cockpit with a rifle laid upon the decking by his side. There was no one else visible, but in front of the Rioguayan was an automatic gun somewhat resembling a Colt, with its muzzle pointing ominously in the direction of the way down the cliff.
"We'll have to rush the 'bus, Uncle," said Peter in a low voice. "It's our only chance."
Uncle Brian nodded, and raising the haversack from the ground, slung it over his shoulder.
"Right," he whispered. "Lead on, but keep a sharp look-out in case there's a man on guard on the cliff. If there is, no firing if it can be avoided, mind."
His nephew gave a sign of assent and replaced his automatic, taking the precaution of leaving the flap of the holster unfastened. Then, with his uncle close at his heels, he crept cautiously along the gully, till he arrived at the slightly rugged ground adjoining the brink of the cliff.
As Peter had expected, there was a sentry postedwithin ten paces of him. The fellow had discarded his flying kit, which was not to be wondered at, seeing that the temperature was somewhere in the region of 120° F. Evidently taking it for granted that, as his comrades and the bloodhound had swept the ground in the neighbourhood of his post, he could "stand easy", he even went so far as to commit the grave military crime of parting with his rifle, for the weapon was resting against a rock. His back was turned to the two Englishmen and—a fact that Peter noted with intense satisfaction—he was rolling a cigarette.
Like almost every person of Latin descent, the fellow was an adept at that task, the cigarette when made being almost semicircular as regards its shape. Then, producing a large box of sulphur matches, he proceeded to set light to the "smoke".
That was the opportunity which Peter was waiting for. He reckoned on the sulphurous fumes causing a little discomfort to the smoker, or at least his attention would be concentrated upon lighting the cigarette, to his own undoing.
Peter had already counted the men engaged in following the useless trail. There were seven, strung out in an irregular line, and by this time quite a quarter of a mile away.
As stealthily as a cat, Peter approached the careless sentry until he was within a couple of yards of him. Then he sprang.
His love of Rugby football had taught him how to "tackle his man low". Before the Rioguayan couldutter a sound or realize what had happened, he was lying half dazed upon the ground, with Peter pinning his arms and Brian Strong pressing the muzzle of an automatic gently against the fellow's temple.
"Ask him," said Peter, "how many men are on board the flying-boat."
Uncle Brian obliged, backing up his request with a slightly stronger pressure of the cold ring of the automatic's muzzle.
"The captain and two mechanics," was the tremulous reply.
"That's what I wanted to know," remarked Peter gratuitously. "Now, Uncle Brian, we'll gag and bind this gentleman, to be left till called for."
Peter proceeded with the operation so rapidly and deftly that it left Uncle Brian wondering where his nephew had acquired that knowledge.
In a very few moments the Rioguayan was trussed like a fowl, his sash and belt coming in very useful for the purpose.
"Now a cartridge, Uncle Brian," continued his relative. Uncle Brian handed him one of the rifle cartridges. This Peter wrapped in a handkerchief.
"Open your mouth, old son," he said.
The "old son", although ignorant of English, obliged instantly. It was patent that he, too, had had experience in the gentle art of gagging.
"And that's that," concluded Peter. "Now for the next act of the matinee. We'll kick off from our hiding-place. It's only an eight-foot drop to thebeach, and a jolly sight quicker than scrambling down the cliff. I'll take the rifle, please."
Silently and cautiously the two men descended the gully until they reached the breastwork separating the rift from the beach.
Peter peered cautiously in the direction of the flying-boat.
The Rioguayan captain was still at his post in the pilot's seat. He was wearing his leather flying-coat but had thrown back the flaps. He was a swarthy, thick-lipped man with hulking shoulders and a head set well forward—altogether a brutal type of humanity.
"It's like potting a sitting rabbit," thought Peter, as he slipped a cartridge into the breech of his rifle. "It's not giving the fellow a ghost of a chance."
Yet, his compunction notwithstanding, Peter's hands were as steady and his eye as clear as an experienced hunter's. It was the first time in his life that he had had a human being covered with a rifle—but it was the only way.
Deliberately he pressed the trigger. The Rioguayan captain did not appear to move. Peter was beginning to think that he had missed, when the man leant forward until his head rested on his arms on the deck of the fuselage—to all appearances as if he were asleep.
Without hesitation, the Englishmen vaulted over the ledge of rocks on to the beach and ran towards the flying-boat. They fully expected to find their way barred by the two mechanics; but the latter had either not heard the shot, or, if they had, had taken it asone of the many fired by the searchers on the island.
image: 05_sentry.jpg[Illustration: PETER TACKLES THE SENTRYPage126]
Gaining the pilot's cabin, Peter peered down the hatchway into the engine-room. The place was empty. Hurrying aft, he found the two mechanics in the motor-room, where the twin engines driving the after pair of propellers were situated.
At the sight of a couple of automatics thrust down the hatchway both men raised their arms with commendable celerity.
"Up—you!" ordered Uncle Brian, indicating one of the engineers.
The fellow complied, his olivine features grey with terror.
At Brian Strong's orders, backed up by an indisputable argument in the shape of a pistol, the man was marched along the alley-way to the gangway and told to go ashore and bring back the grapnel and mooring rope. This he did.
"Now," continued Brian sternly, "you can go and stand over there," indicating a spot close to the mangled remains of the "orange-box". "If you shift from there while you are within range of a rifle, you won't stir more than half a dozen steps. I'm a crack shot.... All right, Peter. Away as soon as you like."
The remaining mechanic was ordered for'ard to start the motors. For the present the flying-boat was to be actuated only by the bow propellers, those aft being required only when proceeding at top speed.
Then Peter, having lowered the body of his victim to the water, took his place in the "office". By thistime the flying-boat, no longer tethered by the rope and grapnel, had drifted from the island before the light offshore wind.
The motors were throbbing tunefully. A forward thrust of one lever was sufficient to bring both propellers in gear. Like a gigantic water-fowl, the aerial craft leapt forward, leaving a feathery wake on the surface of the lake.
When the speed gauge indicated thirty-eight kilometres, Peter manipulated another lever, and, obedient to the alteration of trim of her short, cambered planes, the flying-boat soared into her proper element.
"A 'bus for an orange-box," soliloquized the light-hearted pilot. "Not a bad exchange, eh what?"