"That is a splendid idea; and you might as well vitrify them."

"What do you mean by vitrifying them?"

"Putting the glaze on them, just like the common crocks have."

"That would be simply fine."

The Professor explained the process, which consisted in making the crocks out of the best clay available, and then burning them. Afterwards an intense heat must be made in the furnace, and after soaking the crocks in a strong solution of salt brine, they must be put in and burned again; the greater the heat, the better.

The boys started at this with a will, and when they had arranged to make the crocks they found it most difficult to put them into a round and uniform shape.

"I would suggest that you make a potter's wheel for that purpose."

"A potter's wheel? What is it like?"

"It is the simplest thing imaginable. Do you think, Harry, you could turn out a wooden vessel just the size of the outside of an ordinary milk crock, and turn it with a central stem below, and also have a little pulley on that stem?"

The Professor made a drawing (Fig. 29), which shows just how he wanted it made. In the drawing, A is the cup-shape, which is the size and shape of outside the crock; B is the central stem; and D is the small pulley on the stem. This was mounted in a pair of arms like CC, and a belt was attached to the pulley.

"You have made a very creditable article. Now you may make a flat paddle, and shape one end so that it will be just like the inside of the crock."



The drawing (Fig. 30) shows how it was made, with a cross handle at the upper end.

That day the crocks were turned out in the following manner: The potter's wheel was rotated about sixty turns a minute, and the clay, in a plastic state, was put in the cup-shaped top, and the hands used to force the clay up the side wall. When the crock was formed in as even a manner as it could be by hand, the blade described was used to make the interior uniform.

The potter's wheel is one of the oldest tools known. Its use can be traced back for more than four thousand years, when it was well known by the Egyptians.



Since the day that the boys visited Observation Hill, at the time they discovered the skeleton and fragments of the boat, no attempt had been made to visit the cave. That was the mission when they accidentally made their surprising discovery.

George did not, however, feel that they should again make the attempt until they had a better lighting means than the unsatisfactory candles, and when the supposed petroleum vein dashed all hopes of lighting material from that quarter, the only remedy seemed to be by way of improving their candle-light.

Harry had progressed well in the making of the battery. It was now in a completed state, and he announced that the first tests would be made the next day. In the morning all assembled in the factory, and the sulphuric acid solution was made up.

The Professor inspected the batteries. Ten cells had been prepared, so that they could have, at least, fifteen volts. When all the cells had been connected together—that is, the positive pole of one cell with the negative pole of the other—a wire was attached at each end of the row of cells, at the last electrodes, so as to form the outside connections.

When the two outside wires were brought together and their contact broken a spark was plainly shown, which was an indication that the battery was generating electricity. The boys danced about with joy at this exhibition. From that time forward the battery was one of the most interesting things in the laboratory, and what they finally accomplished with it will be fully detailed as we go along in their history.

George thought he saw a way to make the light necessary for the cave. "Why can't we rig up an electric light now and explore the cave?"

"We might do that, but we have several things to do before we can have light from that source."

"Haven't we the electricity for it?"

"Do you know how many years electricity was known before electric light was discovered? Before we can utilize this agency for lighting purposes, we must make a machine which will produce a vacuum; we must make glass; we must learn to carbonize threads; and the art of blowing glass would be a necessary accomplishment."

"As usual," said Harry, "something must be made to make something that makes something else."

"But can we make electric light without putting it in a glass bulb?"

"Yes; we can make what is called the arc light; instead of the incandescent."

"What is the difference between the two?"

"In the incandescent, such as we talked about making, a thin carbon filament is enclosed in a glass bulb, from which as much air as possible has been exhausted, and when a current of electricity passes through this filament, it is heated up to a white heat."



"Why doesn't it burn out?"

"It does burn out in time. What preserves it, however, for a long time, is that most of the oxygen has been exhausted from the bulb——"

"Oh, yes; I know, there must be oxygen to support combustion, so that the carbon is merely heated up?"

"I am glad you remembered that. The arc light, on the other hand, depends on an entirely different thing. You have seen, no doubt, the long black pencils used in the large lamps. That is carbon also, made out of ground coke, molded and compressed into shape."

"What does arc mean!"

"Did you notice that when we put together the two circuiting ends of the wires in our battery this morning, we could not notice the existence of a current, but whenever we pulled them apart we had a spark?

"Let us now make a little experiment which will show you the arc. You see, I am making a sharp point at the end of each wire, and I will fasten one of the wires so it cannot be moved. Now the other wire will be placed with its point as close to the other points as possible, and so fixed to the support that we can adjust it still closer and hold it. See, the points now touch each other. I will move one of the wires the slightest distance away from the other. There! see the light?"

"But it goes out in a little while; what is the cause of that?"

"The electricity has been burned off the end of the wire, and the distance is now too great for the electricity to jump from one to the other, so they must be moved closer together. That space between the ends of the two wires is the electric arc. Instead of the two wires the carbon pencils are used."

"But how are the two carbon pencils kept apart at the right distance at all times?"

"That is what the invention of the arc light consisted in; to find a means whereby the current itself makes the adjustment necessary to furnish a steady, constant light. When we start to make the arc light the mechanism can be explained."

George's scheme of the electric lamp for the cave had vanished. But the cave must be explored. He was determined on that point.

The yaks were brought out and a start made for the cliffs. After unhitching them from the wagon and unyoking the animals, so they could feed in the meantime, the oil lamps were taken out and carefully examined. The Professor had suggested the advisability of carrying with them two of the spears, which, it will be remembered, formed part of the weapon equipment of their last voyage, and those, with the guns, were considered sufficient for any foe likely to be in the cave.

Harry, on this occasion, volunteered to mount Observation Hill for their daily trip of observation. He returned by the time the yaks were disposed of and the implements prepared, as stated.

"I suggest," said the Professor, "that we keep constantly on the alert now for any vestiges of driftwood, or other objects which we are likely to find along the shore."

As a result the progress was slow, and the scrutiny keen on the part of all. As they rounded the last large projecting rock, just before entering the gorge which led to the cave, Harry jumped on a rock, waving his hand, and crying, as he pointed seaward: "A sail! A ship! See it?"

The agitation of George was beyond all description. Harry kept repeating the words. He was entirely beyond control.

"Be calm; do not become excited. Harry, you are the most nimble; run to Observation Hill: here take the large sheet in the wagon; wave it there, and keep up the signaling; they may see you."

The ship, although far away, was plainly made out, but its character could not be determined. It was evidently a large sailing vessel. Just imagine what must have been the feelings of the party at the sight of the ship, although so far away. Would they see the signal?

In the commotion that followed, what was the Professor doing? He quickly placed two stakes in line with the ship, and watched it patiently. "It is moving to the west."

George's curiosity induced him to look over the Professor's shoulder, and thus enable him to follow the movement of the boat, and by means of which he could see the sails slowly move past the distant stake.

The Professor scarcely moved. "What is Harry doing? Is he still signaling?"

"Yes; he hasn't stopped since he reached the hill."

The stake nearest the Professor was again moved over a trifle as the ship moved on, and they watched and waited.

"Why, the ship hasn't moved for the last ten minutes."

"It seems not," was the Professor's response. Again they waited. George walked to the stakes and back again. He stepped aside to look at Harry on the hill, and again returned to the observation stakes.

"Singular that the ship hasn't moved in twenty minutes or more."

Then, enthusiastic at the mere thought, he cried out, as he ran toward the Professor: "Do you think they have seen our signal? Have they stopped; and are they returning?"

"Either that or they have changed their course, and are now leaving us dead ahead."

This was a blow to the poor boy, whose hopes, brought about by the apparently checked motion of the ship, were now dashed to the ground, when the Professor continued: "They are sailing away, I am sorry to say."

He left the observation stakes. Poor Harry was still signaling frantically. The Professor told Harry that further effort in that direction would be useless, and he slowly and sadly came down the hill.

They looked at each other most sorrowfully, and the boys could scarcely restrain their tears, while the Professor carefully avoided their gaze, or seemed not to notice their grief.

"It is one satisfaction to know," said Harry, as he dolefully looked across the broad sea, "that vessels do come this way, and that it is not out of the world entirely."

George quickly recovered. "Why not make a big signal flag for Observation Hill?" This was seconded by the Professor.

"And while we are about it why not make a good old American flag?" was Harry's comment.

The cave had been forgotten in this incident. When their wondering and questionings had ceased, the descent was made around the point, and the entrance soon reached.

The two lamps were now lighted, and the explorations began.

"I think it is advisable," was the Professor's first observation, "that we go in a hundred feet or so, and then mount one of our lamps in a conspicuous place. We can then proceed with the other as far as the water, and if any accident happens it will not cause trouble to both of the lights. We can always have one of them to fall back on."

When they had gone the distance determined on, a secure ledge was selected, and Harry placed the light so it would cast its beams along the cave.

"Be careful now, we are near the water."

The Professor had now the other light, and the boys led the way, so the beams from the light shone past ahead of them. They went beyond the point where the water had been found previously, but there was no sign of it. The course of the cave now changed to the right, and the floor of the cave went downwardly at a slight descent.

The Professor suddenly restrained the boys. "Wait a moment; the light behind us should be brought forward to this point."

George went back and brought it up, and after some delay a place for it was found. The two lights now plainly showed a sudden enlargement in the area of the cave, and above them hung what appeared to be huge icicles, giving the interior a weird appearance. Still no water was in sight.

"The white substances we see all around us indicate that above us the rocks are limestone, and water, in coming through, has acted on the stone so as to form carbonate of lime, or chalk."

The single lamp was now sufficient to light up the interior, which looked like a domed iceberg, with all sorts of fantastic figures standing out in bold relief, which were contrasted by the many dark recesses irregularly scattered about everywhere.

"I see an opening beyond," was Harry's remark, in a suppressed tone.

The contracted opening was to the left, and he quickly made his way over the uneven floor to that point. "The water is beyond, and I hear something there."

George quietly moved forward. The light from the Professor's lamp glistened on the surface, and rippling waves were easily distinguished.

"What has become of the light we had on the perch?" was the Professor's startling inquiry.

The boys looked back. It was not there. Probably it had gone out.

"We must not go on until we have relighted it," was the Professor's caution.

George went back. The light from the Professor's lamp still threw its rays back to the ledge, which was not more than a hundred feet from their present location. "I can't find it. It is not here, and I know I put it on this ledge. Here is the piece of lime I put up against it."

Too startled for words, Harry drew back from the opening. Without further conversation he and the Professor retraced their steps toward George, who was now frantically searching every crevice.

"That is too bad. Are you sure this is the place?"

"I am positive of it."

The boys looked at the Professor. He knew they mentally asked whether they should proceed with the single light. "I think it would be unwise to go farther with one light only. If we can do no better we can make a half dozen lights, and light up the whole cave. I am just as much interested in it now as you are."

They were about six hundred feet from the mouth of the cave, as nearly as could be estimated.

"Before we return we might as well chart the cave, so we shall have some idea of its crooks and turns. Have we anything to measure with? If not, have you a cord, so we can get some idea of distances?"

George held out one of the spears, which was about five feet long.

"That will answer," said the Professor. "Let us call this five feet long for the present. The first thing we must do is to establish a base line. But what shall we do for something to mark our chart on? I haven't a bit of paper."

Here was another difficulty. It would be impossible to make tracings on their clothing. Harry's wit came to the rescue. "I have it. Why can't we break off a piece of this chalk. Probably we can find some smooth piece that will answer."

"That might be done," was George's answer, on reflection; "but what can be used to mark on chalk?"

The Professor was now highly amused. "Can't you think of anything we have here which will answer?"

"I haven't had a pencil, or anything except charcoal, since we touched this wonder island."

"We have something here that is used among all civilized people the world over for marking purposes." The boys opened their eyes in wonder. "I have it here," said the Professor, looking at the lamp.

"The lamp?"

"No, not the lamp, but what is in the lamp."

"The oil? Where can we get anything to mark with in the oil?"

"We have been making a marking material all the time we have been in the cave, and you are just as well acquainted with it as anything you know. It is the soot from the burning oil."

The boys laughed, not at the information, but at their stupidity.

"Yes; the soot is carbon, and the best soot is made by imperfectly burning oil, or fat, or any other fuel which has a large amount of carbon."

The boys found several pieces of flat chalk, one of them a little over a foot long. This was held above the flame of the candle until covered with soot.

"The first thing to do is to establish a base line. This we will mark A on the drawing. Now, starting from the point here where we lost the light, you may measure along the line to the west, we will say, until you get to the other end of the chamber. Twenty-five measures of the spear? That makes the chamber 125 feet long, and it is about 90 feet the other way. Let us roughly outline the floor plan. Now go out toward the mouth of our cave, and measure off 50 feet. Stop there. You see, I have marked the line A and have laid down the slate slab so that this line is exactly on a line with the one you have measured along the chamber. The point B, 50 feet from here, which you have just measured, makes an angle, C. I will now take the slab to the point B, and you may measure off 50 feet more, and we will call that D. That gives us another angle line, E. You see, at every point we establish a new base line. C is the base line for the line E, and so on all through the cave."



All the measurements were made on the plan outlined, and scratched on the sooted slab.

"One thing more we must observe. As we are marking the successive points, you will notice that I took particular care to observe the side walls of the passageway, so that I could roughly outline them, noting the distances from the various points, and in a crude way marking out the irregularities between the points."

The chart interested the boys so intensely that the disappearance of the light did not again recur to them until they emerged from the mouth of the cave, when it all came back again, with added wonder and speculation. How many more mysterious things would present themselves!



CHAPTER XIII

THE EXCITING HUNT IN THE FOREST

They returned to their home with conflicting emotions. It had been an eventful day. They had a glimpse of the outside world, and an experience below the surface of the earth. Both were unsatisfying. They could explain the one far away on the sea; but the other, close at hand, was a mystery.

"How do you account for the water being so far away from the mouth of the cave?" was George's inquiry after the evening meal.

"Haven't you noticed that we have had no rain for the past five weeks?"

Such was, indeed, the case. The boys had not been observant, like the Professor.

"Evidently the water is supplied from rains, and the floor of the cave permits more or less of the water to leak through, so that, in time, if we had no rains, the cave would be entirely free of water."

"But how about the animal in there; if it is a water animal, how did it get in; and if the water ever dries up, how can it live there?"

"There may not be any subterranean connection directly with the sea, and the animal has been trapped there; or it may be able to reach the sea in the cave at any time, by some underground channel."

"How far do you think the cave goes in?"

"That is one of the impossible things to say. It may extend for miles. Like yourselves, I am curious to know all about it, as soon as we can make further investigations. In the meantime, don't forget about the flag."

"I had forgotten that. I am willing to start on it in the morning. How large should it be made?"

"We should make it a regulation flag, by all means."

"Let me see; how many stripes must we have?" said Harry.

"I know; thirteen."

"Yes; and they must be red and white."

"That is correct," responded the Professor; "but do you remember how many of each?"

The boys were silent.

"The top and the bottom stripes are red, and the intervening ones white. What do these stripes represent?"

"The original States."

"I see you have a pretty good recollection. I remember a class of over forty boys, on one occasion, which had only three boys who recalled that. Then we must have a field of another color, up in the corner."

"That is the blue field, with stars on it."

"Yes; but how many stars?"

"A star for each State."

"And how many States are there now?"

There was no response to this. How many boys or men, even, can tell offhand the number at the present time?

"There were 48 before we sailed. How many, if any, were added since I do not know."

The next day the boys were anxious to set to work on the flag. There was plenty of the ramie cloth at hand, but it was quite yellow. George noticed this, and said: "It seems to me we shall have to be content with making the flag red, yellow and blue, that is, if we can get the red and the blue."

"No," was the Professor's rejoinder; "we must make it red, white and blue."

"But how can we make the ramie cloth white?"

"By bleaching it."

That was a new idea; to make white cloth.

"How can we do it?"

"Wet it and put it in the sun. If we want to hurry it up we can use some chloride of lime."

"But where is the chloride of lime?"

"Do you remember that black ore we have in the laboratory, which is called manganese? If we put some of the sulphuric acid on that a gas will be formed, called chlorine, one of the most powerful bleaching compounds known. We can use it in that form, or subject some of our lime to the gases, and in that case make chloride of lime."

The decision was to make the flag sixteen feet long and nine feet nine inches wide, so that each stripe would be nine inches wide. The blue field would be five feet wide and seven feet long.

This was certainly a task, and the boys were directed to prepare four strips of red and three strips of white, each nine feet long, and also three strips of white and three strips of red sixteen feet long. Four of the short strips and three of the long strips were then laid aside to be dyed red. The other strips were put out to bleach.

When all this was prepared George was troubled about the colors.

"Professor, I do not see what we can use to make the blue and red colors."

"I think we are fortunate in having one of the varieties of the madder plant all about here."

"Is that a good dye plant?"

"It is a plant that is more extensively used for dyeing than any other in the world. For many years, until the products from petroleum began to come in, it was the only source for the red colors, because of its permanence. The dye is so powerful that it will turn the bones of animals red, if they are fed on it, and it also colors the claws and beaks of birds."

"Have you seen any of it here?"

"There is plenty of it growing here. You cannot mistake it. It is the plant with the elongated, smooth-edged leaf, which grows on the main stem, from which the small, thin stems branch out that carry the little red flowers."

"I know what you mean; let me get some of them at once." And George was off after the plant.

Meanwhile Harry was busily at work cutting out the double set of stars required for the blue field.

Several days before this George had prepared the roots of the chicory plant, as will be remembered, and it had been dried, and was ready to be ground up. At the noon meal he served the first cup of "coffee," to the delight of Harry, who was completely taken by surprise, and afforded much amusement for George and the Professor.

"It seems to be rather strong," was Harry's only comment, "and even if it isn't real coffee, it is good enough, I assure you."

"Wouldn't it be injurious to take too much of it?"



"Exactly with this as with everything else. It is not the use, but the abuse, that causes trouble. Of course, chicory does not have the soothing and hunger-staying qualities of the real coffee, but the bitter principle in the root is a tonic, and the extract is used as a medicine for that purpose. The leaves of the endive, of which we are using the roots, make a most delicious salad."

"Don't many people use this as a kind of an intoxicant?"

"If used to excess it has an exhilarating influence, on account of its tonic properties."

"I have often thought it was wonderful," said Harry, "that people all over the world have some kind of a weed or plant that they use to stimulate themselves with."

"There seems to be a universal instinct in man to select the strong and bitter principles for that purpose. The aborigines of Central America used rolled tobacco leaves ages before Columbus was born; and the coca leaf, chewed by the lowest orders of the Peruvians, was for ages, and is now, their main source of strength and comfort. So opium, hemp and the betel-nut have been used by eastern Asiatics from the remotest antiquity; and the same is true of the pepper plants of the South Sea Islands and the Indian Archipelago; also of the thorn apples used among the natives of the Andes, and on the slopes of the Himalayas. In northern Europe the ledum and the hop have been so used, and in Siberia the narcotic fungus has been eaten from time immemorial."

At that moment Baby appeared on the scene, his hands and one side of his head dyed a beautiful red, presenting a ludicrous appearance. The first glance at him was one of astonishment; but realizing that he had been testing George's newly made dye, all burst out in laughter at the amusing sight.

"You really look like a red angel," was George's greeting, and Baby seemed to relish the joke. From that time forward Baby's name was "Red Angel," but it took him some time to learn what the new title was. It took him much longer to acquire it than it did to learn what honey meant.

"Red Angel is certainly a very smart little chap," said the Professor, with a laugh, "because he was really doing what is done in the dyeing art and in chemistry every day, furnishing a test sample."

"Test sample; what is that?"

"In the art of dyeing it is the custom, before commencing to dye goods, to make a test sample, and all goods dyed must come up to the standard set by that sample. That is called the 'test sample.'"

"But how do the chemists use it?"

"In the analyses of chemicals one of the processes is by what is called the color metric test—that is, the test by color. The chemist makes a solution with a known quantity of the element in it which is of full strength and purity, and is therefore of a well-defined color. Now, if any substance is to be analyzed, the same reagent is used in the tested sample as was used to make the well-known sample. The color of the unknown sample is then compared with the known sample, and the quantity determined by the difference of color in the two."

"What do you mean by reagent?"

"A substance used to effect a chemical change in another substance. For instance, what is called Nessler's Reagent is a substance which, if put into water, will detect one part of ammonia in twenty million parts of water, and give a perceptible reddish-yellow tinge."

"Well, Red Angel has certainly made a good test sample for us; isn't that a good color?"

The blue color was still wanting when the other parts were ready, and the Professor came to the laboratory with a sample of bitter-sweet, the common hedge plant of North America. The boys both recognized the plant and were surprised to learn that it contained a dye suitable for their purpose.

"We can use this or take some of the copper ore, that is, the blue vitriol part of the ore, and by putting it in a lime-water solution a beautiful blue color can be obtained."

The flag, when completed, was really a work of art. They gave many days to the task, and were proud of it. The question of a suitable pole or flagstaff was one which now absorbed their energies. As nothing of the kind was found in the immediate neighborhood, it was suggested that on their regular hunting day it should be made a part of their duty to find a staff worthy to be installed. The trips to the cave, and the absorbing work of preparing the flag, had so taken up the time, that they had entirely forgotten the regular outings.

On this occasion they insisted that the Professor should accompany them, and George declared that the only place available for a good pole would be in the forest below the South River, where they had shot the ocelots.

The yaks were prepared, as usual, and it was a merry party which started off on that bright morning for the forest. They did not, you may be sure, forget the spears and the guns, and before leaving home Harry thought it would be a good idea to provide a small two-wheeled truck, which could be used as a trailer, for the pole.

On the way down, Harry said: "How large a pole shall we get?"

George had his opinions, as usual: "Let us get a pole at least 50 feet long. We must have something which will match the flag."

"A pole that length will be a difficult matter to raise; have you thought of that?" was the Professor's observation.

"Can't we rig up something to raise it with?"

"Yes; and for a pole a hundred feet long, if necessary."

The Professor made no further objections. Reaching the South River the yaks were tethered, and taking advantage of the raft which they had used on the first trip, they were soon on the way into the forest. On this occasion they took a course to the right of their former exploits, the desire being to acquaint themselves, as much as possible, with the topography of the country toward the falls. Soon they came within sight of game, squirrels, woodchucks; and many familiar varieties of birds were seen on all sides.

What interested the boys most was an animal about three and a half feet long, and almost three feet high, which they saw at a distance.

"What is that, Professor?"

"It is a giant ant-eater, found in many parts of South America."

"What a big bushy tail he has."

"He uses that in a peculiar way. When he sleeps he lies on one side, rolls himself up so that his snout lies on his breast, places all his feet together, and covers himself with that bushy tail. As the hair of the tail resembles hay, or the surrounding dried grass, it is likely to be passed by without being noticed."

"I wish we could get a shot at him."

"There is a fine pole," said Harry, whose keen interest was as great in that quarter as in the hunting.



It was an exceptionally fine specimen of shell-bark hickory, and the base was nearly six inches in diameter, but it was as straight as a line, apparently, and it was fully thirty feet to the first limb.

"You couldn't get a better pole; but hickory is one of the heaviest woods, and being green, it will be a task to raise it. It weighs, dry, about 45 pounds per cubic foot."

"What is the weight of a cubic foot of water?"

"About sixty-four pounds."

"How much do you think that pole will weigh when it is trimmed up?"

The Professor, after carefully surveying the tree for a time, answered: "It will weigh fully 400 pounds, but I am in favor of taking it, as we know shell bark is a good American tree, and it is the kind of wood we usually select on account of its strength. I know it will resist any winds likely to come our way."

It was at once cut down, and on measuring was found to be 58 feet up to the branching top, at which point it was not less than two inches in diameter.

"Cut it off above the last crotch, as we shall want that part to attach the top pulley between."

Now that it was cut and trimmed, the problem was to convey it back to the river.

"Do you think we can induce the yaks to swim across the river?"

"That's a capital idea, Harry, let us go back and try it."

"While you are getting the animals I shall do some investigating," said the Professor.

The boys crossed the river and took the two-wheeled truck across. "It might be amusing to the Professor, if he found we had taken the truck across before we knew whether the yaks could be induced to go over." Harry laughed at George, and answered: "How shall we manage it? We had better keep them yoked, I suppose."

After some urging, they were driven to the water, the boys having tied a rope to the yoke before they went into the river. To their great surprise and relief, the yaks made no objections, and immediately started out at a great rate for the opposite shore, and before they had gone twenty feet were swimming. The boys in the raft held on tightly and were drawn across without further trouble.

As they left the river for the trip, they distinctly heard a shot.

"I wonder what the Professor has shot? Did you hear him?" They listened intently. The shot appeared to come from a point considerably to the left of the place where the pole had been cut, but they paid little attention to that. After they had gone halfway another shot was heard, this time at a point which indicated that the Professor must be some distance away.

As anticipated, the Professor was not in the location of the pole.

"I don't think the Professor expected us back so soon," was Harry's suggestion. "Let us rig up the pole and hitch the team, and by that time he may be back."

In less than a half hour this was done, ready for a start; still no signs of the Professor.

"I think we had better fire a shot to let him know we are here."

"Singular we didn't think of that before; here goes." Waiting fully a quarter of an hour after the shot, they were surprised at not hearing any response from him. "I wonder," continued Harry, "if he has met with some accident?"

"We heard it in this direction, didn't we? Don't let us waste any more time. Get the guns and ammunition. Hurry up; and let us take a spear; it may be useful."

Each boy took a spear, as a matter of precaution, and set out. At intervals the boys shouted, and after wandering about for fully a half hour, determined to try another shot. This was answered by a shot apparently from the direction of the team, and the boys turned about and hurriedly made their way back.

It happened that the boys had actually lost their way, and in the excitement all sense of direction. The Professor had made a complete circle and the boys in their wanderings had executed a complete loop within that circle, and were actually going back to the river instead of to the team.

"I can't understand this business," said George, in a despairing tone. "We have traveled far enough to get back to the team twice over. Let's try another shot." It was answered by a shout from the Professor, close by, to their left, and when they appeared in sight he was seated on the log leisurely driving the yaks, laughing in a quiet way, and apparently not noticing the discomfiture of the boys.

"We thought you were lost," said George; "didn't you hear us firing?"

"How does it happen you are going in this direction?" was the Professor's quizzical remark, which he uttered with a faint suspicion of a smile. As the boys did not reply, he continued: "Did you expect to find the team at the river?"



Of course, they all had a good laugh at this, because the direction they were taking, and the position in which the Professor found them, were sufficient to indicate that they were really lost, and that he knew it.

"I felt satisfied," was his final remark, "that you had not a well-defined idea of your direction when you fired the last time, but you will learn in time how to keep your direction, and what is more, you will never again permit an excited condition of the mind to make you take a crooked path."

The boys looked wonderingly at the Professor.

"How," asked Harry, "does an excited mind make anyone take a crooked path?"

"When the mind is excited, it is, for the time, deranged, like soldiers, frequently on the field of battle, who are wounded, without having the least knowledge of it. The sense of direction is a well-developed trait in some people; in others, it does not exist at all. But in the case of either, the moment the mind is excited, it becomes abnormal; some lose the ability to judge distances, some are unable to talk, and others can't do anything but talk. All judgment for the time disappears. Now, take that person in a forest, and highly excite him, and he has absolutely no judgment of distance or direction, and is not in a good position to mark and follow a course with intelligence. I have spoken thus fully on the subject, in order to warn you, that under no circumstances should you ever set out on such a mission as you have with the least cloud of excitement. It is far better not to go at all."

It was a warning the boys never forgot.



CHAPTER XIV

THE RAISING OF THE FLAG AND ANGEL'S PART IN IT

On the return home that evening they were surprised to find Red Angel absent. Frequently he would go with them on their trips, but he was purposely left at home on this occasion. He had ample opportunity to roam at will during their absence, and had never strayed away.

"It is very singular he cannot be found. I searched the house, the shop, and the cattle range, and he is nowhere in sight."

It was a grief to all to miss him, as all had learned to appreciate his mischievous tricks, and George had taken a delight in "educating" him. Probably now, that he had grown to a more mature age, the spirit of the wild life possessed him, and he had taken French leave at the first opportunity.

George missed him more than Harry, because as cooking was one of George's accomplishments, and as honey was the weak spot in Red Angel, the kitchen was an attraction, and the reward for service in the kitchen was this delicious sweet.

Their stock of this was running low. George was not as liberal with honey of late, and after ruminating on the subject of the disappearance, he concluded that Red Angel had cause for "running away."

The next morning while at breakfast, who should appear at the door but Red Angel, his long fingers and palms holding a quantity of nuts. He evidently saw that the welcome was most enthusiastic on the part of all. With the utmost gravity he shambled across the floor and deposited the nuts on the table and took his usual place in the most matter-of-fact way, and commenced on the nuts as though it was part of a solemn duty.

George's hand reached out for the honey; Angel saw it, a quizzical look came on his face—a real orang smile—and he forgot about the nuts.

In a spirit of fun George helped himself without offering any. This was too much for the animal, and with a shrewd, calculating look he pushed the nuts over to George.

Did he get any honey after this? George could not resist this appeal; and after Angel got it, and George helped himself to nuts, the Simian approval was very marked. Do you think he reasoned?

Preparations must now be made for "pole-raising day." In the absence of a sufficient amount of rope the last bearskin was cut up into strips, as it was necessary to have nearly a hundred feet, and the bearskin was a much-needed addition to the small quantity of ramie cord which they had on hand.

The Professor took a keen interest in the proceedings. "We must get a half dozen forked poles of good wood; they should be of different lengths, to support the pole as it goes up. Then, Harry, as we have a pretty tough job before us, I suggest that you make two capstans, something like those you saw on shipboard, around which the two raising ropes can he wound, each to have a crank, and a means for holding the crank at any position."

The preparations occupied the greater part of the day. Several boards, five feet long, were required, and at least a dozen stakes to hold the capstans in position.

Early the following morning the yaks were brought out, yoked up, and the pole and truck hitched on. A luncheon was provided, the flag and all paraphernalia assembled and loaded, and Red Angel invited to attend the ceremonies.



Reaching Observation Hill, a spot for the pole was selected, and a hole three feet in diameter and five feet deep was laboriously dug out. It was, indeed, a trying task, with the tools they had, but it was a labor of love. It was more than that to them. They were now making preparations to notify the world that they still lived.

The top of the pole had been provided with a pulley, which was mounted between the crotch, and a guard put over the pulley, so it would prevent the halliards from coming off. When it had been placed in position, with the foot across the hole, the two boards were stood down in the pit so the end of the pole was against them. The halliards were then strung over the pulley and looped down, and the three ropes were attached to the pole, twenty feet from the lower end. Together they raised it up, so that it was about five feet from the ground at the point where the ropes were tied. Two of the ropes were then carried out past the hole, and branched out, and attached to the capstans, while the other was allowed to hang. As the capstans turned, the pole was gradually drawn up, and the Professor stood ready with the forked standards to prevent the flagstaff from falling back. In less than an hour it was erect, and the work of tamping in the dirt and stone around the base was in order, and soon completed.

And now for the flag!

"Tell us, Professor, why the attaching of the flag on the cord, or halliards, is called bending it?"

"The term comes from heraldry, and it originally designated two diagonal lines across the field of an escutcheon. Later on, sailors bent the ends of the flags or ensigns on the halliards, or around the yards, and also called the fastening of a cable to the anchor a bend; a knot is also designated by them as a bend; the form of the ship from the keel to the top of the side is called a bend, as, the midship bend."

A strong rope had been seamed in the end of the flag, and eyelets worked at intervals, so that the task of attaching it to the halliards was soon performed.

"The raising of the national emblem for the first time in any new country has always been regarded as an event of the greatest importance, as it represents sovereignty and responsibility. On this occasion," said the Professor, as he removed his hat, "let us honor the flag with appropriate ceremonies."

At that moment Red Angel concluded he would also take part, and in an instant was at the pole and scrambled upwardly. When the top was reached he caught sight of the wheel. It moved. Every time he grasped the rope the wheel would turn.

This seriously interrupted the program. The Professor could not help laughing. A moment before he was particularly grave, and the boys had no feelings of mirth; but now this new element in the proceedings added gaiety to the occasion.

"Come down, you rascal! Come down! Do you hear me?" cried George. Red Angel didn't hear. He hung there and smiled; yes, smiled, as he looked down, while playing with the wheel. "We can't put up the flag while he is there." George walked over to the wagon, and took out the honey pot. Red Angel saw it, but made no motion to come down. The honey pot was held up as an inducement, but there was nothing in the world so fascinating just then as that wheel.

Harry and the Professor laughed at the situation. Just to think of it! An orang-outan actually preventing a foreign power from hoisting the emblem of possession over his native land! It was too ludicrous for words.

George actually became almost hysterical as he threw himself back on the seat of the wagon and held up the honey pot, while laughing. "What do you think that little scamp has been doing? He has eaten every bit of the honey." That only added another fit of laughter, and when it subsided, and George could recover his voice, he added, "and wasn't this a smart thing to do?" as he held up the vessel.

"What?" asked Harry, momentarily straightening out his face.

"He actually put the lid back after he got through."

But this could not last indefinitely. No one suggested a remedy, if there was one. The United States must take possession in the proper way; hats must come off; the flag must go up slowly, and the band must play the national air;—the music, they had not thought of it before.

"Can you climb the pole, George?" asked the Professor.

"I think so, with the aid of the halliard."

He approached the pole. "Do you hear me, Baby, come down! Come down, I say!"

Red Angel saw George's design, and without saying a word he slowly descended, shambled over to the wagon, and hanging on the side of the box, looked around to the company in the most reproachful manner.



The hoisting of the flag was, indeed, a solemn thing, but it had its amusing side, and when, with uncovered heads, the flag went up to the masthead and stopped there, the Professor said: "We should have had music to make it more appropriate, but as we have no band, let us sing 'The Star-Spangled Banner.'"

The boys were both good singers, as the Professor knew. The song was started, but before the first line was finished, they broke down and tears began to come; the Professor, with his hands clasped and head bowed, did not look up, nor was he surprised when they stopped. The boys had a suspicion that even he could not have carried that song a single bar. They were powerless to go on.

When the Professor did look up and gaze on the flag, the boys saw his tears; they were ashamed no longer, and their eyes looked up, too.

In a voice which sounded almost strange to the boys, the Professor said: "We take possession of this land in the name of the United States of America, and give notice that we shall defend the same against all powers."

Then, as the beautiful flag unfurled itself, and threw its waving shadow on the ground that it now protected, they looked down, and there was Red Angel, close beside them, looking up at the flag as though he understood what it meant, and his silence gave consent to the solemn act which transferred his allegiance to a greater power.

As they were about to descend the hill the Professor called them to a halt. "Do you intend to leave the flag at full mast?"

They had entirely forgotten to half mast it. "And now," said Harry, "if they can't see that flag we'll make one big enough next time."

As they went down the hill, they could not help looking back over and over, to admire the flag and the pole, and everything connected with it. They knew every thread and every piece of it. Somehow it seemed to be a part of them.

There was always a sentimental streak in George. "I can't help thinking that is the most beautiful flag in the world; I suppose other people think the same of their flag. How did flags come to be used by people?"

"The flag is the successor of the banner, which is taken from the Celtic word 'band.' The Bible mentions banners, showing they were used early in scriptural history. The banners of the Romans, used in their warfares, were essentially different from modern flags, colors and ensigns; they were carvings of wood or metal, some of them representing eagles, like the Persian standard described by Xenophon. In the Middle Ages it was a connecting link between the military and the clergy. The crescent and the cross symbols typified the two great contending forces of the world at that time."

Returning to their home, tired with the exertions, they sat in the living room and talked over the events of the day. Somehow, they felt that the day was too sacred to be desecrated with further toil. They congratulated each other at the success in raising the pole, as that was a matter which had given them a great deal of concern.

Ever since the day on which they commenced work on the electric battery the boys deplored the lack of glass. If they could make that it would be of such immense importance to them in many ways. It would be of great service for their tableware; they could use it for their electric work, which interested them more than any branch to which their time had been given, among the mechanical arts; with that they could make thermometers and testing instruments; and give their house the air of a modern home, because windows could be put in.

"Will it be difficult to make glass?" asked George.

"It is an exceedingly simple matter to make glass—that is, to fuse or melt it. The difficult part is the art of making it, either by the blowing process, or by making the flat forms, like window panes and the like. Owing to the simplicity in preparing it, the making of glass articles was known at a very early date, certainly fifteen hundred years before the beginning of the Christian era. In the first stages only opaque glass was produced, and it was not until eight hundred years later that the first transparent product was manufactured. Under Pharaoh it was one of the products extensively made and exported to Phonecia and other Mediterranean ports. Five hundred years before Christ, Aristophanes mentions glass or crystal vessels, but as its value at that time was next to gold it could not have been a common article."

"What is glass made of?"

"Simply common sand. Sand is the ground up particles of quartz, and may be found almost everywhere. The principal thing is to get the pure quartz. In connection an alkali of some kind must be used."

"What is an alkali?"

"A substance which is the exact opposite of an acid. Potash, soda and hartshorn (or ammonia) are the best known. They have most remarkable chemical activities, and an alkali united with an acid entirely neutralizes or destroys the activity of both. The compound produced by the union of an acid and an alkali is termed a salt."

"What is the effect of using an alkali with the quartz sand?"

"Quartz possesses all the qualities of an acid, so that when the alkali is fused with the quartz a neutral substance, unlike either, is formed."

"What kind of alkali is best to use?"

"That depends on what it is to be used for. Quartz and lime make a fine window glass product. Bottle glass is usually made of soda and quartz; window glass is also made of quartz, soda and lime; plate glass of quartz, lime, soda and potash; and flint glass has only the alkalis, potash and oxide of lead."

"Well, for our purposes, wouldn't it be better to make the glass out of quartz and lime if windows can be made out of it?"

"By all means, for several reasons: We have the lime on hand, and also because it makes a very hard article."

"What can we melt it up in?"

"The clay retort or crucible will just be the thing for the purpose, and the first thing in the morning I will make a tour to a point close at hand, where I think we shall be able to get a good quality."

The boys were astir in the morning earlier than usual. They had a new impulse—something to learn and to do. Harry busied himself with putting the crucible in order, and in getting the fuel. George, after his usual morning's work, brought in the lime, and broke it up preparatory to grinding it up into small particles, so that it would intimately mix with the sand.

Within an hour the Professor returned with several samples of sand, either of which, he thought, would make a good article. The yaks were hitched up, and George went with him to get a good supply.

"How much do you think we ought to make up at first?"

"Several gallons of the sand will do for the experiment."

"What kind of article should be made with the first trial?"

"We might make some window glass. It is true it will not be transparent, but it will be translucent, and so will give us light, as well as though it should be transparent."

"What is translucent glass?"

"Where the surface of a cast plate is polished the material is such that you can see through it, but if it is left rough it is impossible to see through it, although it will permit light to go through. The term applied to such glass is translucent."

"If light will pass through, why is it the eye cannot see through it?"

"A powerful magnifying glass shows that the surface of unpolished glass is formed by a layer of crystals, or of sand, with the faces projecting out in all directions and at all angles. The result is, that a beam of light from the eye strikes one or more of these faces and is diverted from a straight line through the glass. As all the rays are thus changed from a direct course, confusion results, and the eye distinguishes nothing."

Several bushels of the sand were brought to the laboratory, and the Professor then directed the preparation of a half dozen slate slabs, each slab being nearly two feet square. He explained that in practice iron plates were used, but as they had nothing of that kind available, slate would answer admirably.

"The slate slabs must be heated, and when the fused material is poured on the slabs, the heat must be kept up for a short time and gradually cooled down."

"What is the object in doing that?"

"If cooled too suddenly the plates, will crack, but by heating the slates and then cooling them down gradually, we anneal the glass, in a measure. You remember how we annealed the steel by gradually cooling it down? Glass, however, cannot be annealed so that it will not fracture, although attempts have been made for years to find a means for doing it. The man who can discover a process that will enable it to bend without breaking, can command any price for the discovery."



CHAPTER XV

MYSTERIOUS HAPPENINGS ON THE ISLAND

The Professor supervised every part of the operation with the utmost care. "Before the plates are heated you must put a raised margin around each slate square, so the molten material will not run off."

"How high shall we make the margins?"

"About a quarter inch above the surface of the slate."

"As we are now ready to heat up the crucible, how shall the materials be mixed?"



"For this trial, measure out eight quarts of sand and two quarts of the lime, and after depositing it in the crucible, we are ready for the heat."

In a short time, with the assistance of the blower, which has already been described, the sand began to melt. It was now stirred so that the elements were thoroughly mingled. During the melting period the dross or impurities which came to the top were skimmed off, and when no more of the impurities collected the Professor stated that they might remove the crucible and pour the melted mass into small pockets, which they had previously formed with clay.

"Why not pour this on the slate forms we made?"

"Because we must know that we have a good sample of glass, and for the further reason that the product we are now to make should have some glass in it that has already been fluxed before, and we now have such a manufactured material."

The material which had been cast in the pockets was broken up with a hammer, as soon as it had cooled, and its appearance noted.

"I see we shall have to use less lime."

"Why?"

"You will note that it is too white or milky-like. This shows too much lime and consequently it is very brittle."

"Suppose, on the other hand, there was too little lime, what would be the result?"

"We should then have a glass which would not hang together at all. In the one case, as with the present sample, with too much lime in it, we have made a product which is closely allied to the alkaline base; and if we had, on the other hand, too little lime, we should have something which is nearly like quartz, hence not suitable for our purpose."

"It seems, then, we have to do in this case just as Red Angel did, make a test sample?"

This allusion to their pet caused a smile all around.

Since the trip made by our colonists two months before they made no effort to gain any additional knowledge of their island. What they really knew of the country, aside from two of the trips made in the interior, under very unfavorable circumstances, was of no value as a means of locating the natives.

That the island was inhabited there could no longer be any reason to doubt. The fire plot on the banks of the Cataract River, the lights near the woods beyond the West River, the finding of the arrows, and the mysterious use of the boat which had so strangely disappeared from the falls in South River, to say nothing of the removal of the flag and flagstaff, were evidences which could not be disregarded.

The further investigations which they must make for their own safety was one of the impelling steps which determined them to build another boat. The discovery of the wrecked portion of the life-boat and the decision to utilize the recovered portion for the new craft had facilitated their preparations somewhat, but there was still a great deal of work to do.

They had six imperfect guns, as they called them, mere pistols, muzzle-loaders, with barrels eight inches long, and the powder was not the best which could be made. Everything was crude and imperfect, and to boldly venture out among savage tribes with such an equipment would not be wise.

All these things were considered in their conferences. But another matter was suggested by the Professor, which carried some weight. A sail had been seen by them. There could be no question on that point. Other ships might come again, and now that they had a flag of such proportions that it would be seen miles further than the original one, it was possible that the opportunity of rescue might be more likely from their side of the island than anywhere else.

It was certain that if a ship should, in their absence, reach the port, and even discover their home through the instrumentality of the evidence which they had left at the signal flag, there was no assurance that the vessel would await their return, or undertake the mission of rescuing them from the savages, if they should be so unfortunate as to be captured.

It was a most distracting thing to solve. It was not only perplexing, but exceedingly trying, to feel that at any moment a visit might be expected from the natives.

Nevertheless, after all considerations, and giving due weight to the likelihood that some ship might visit them, the building of the boat was decided on, and it was to be of such a character that it could circumnavigate the island. They believed it to be their first duty to do this.

This was the Professor's view: "If we can build a boat large enough, and make it of sufficient strength to carry us and the provisions we must take with us, on such a voyage, we should, at some point in our tour, find the natives, and determine their character."

"But, supposing, Professor, that they discover our boat and should pursue us?"

"My reply to that is, that our vessel must be made of sufficient size and strength to outsail them. My opinion is that the most they have is canoes, and we could readily cope with them. The difficulty is this: If we should be discovered, their curiosity, to say the least, would be sufficient to cause them to trail us along the shore, and it would be exceedingly uncomfortable to have them follow us around the shores to our home. Afloat, in strange localities, on an uncharted sea, at night, is a trying situation with a sailor, even though he has all the instruments of navigation at his command. To go ashore, under the circumstances, knowing that the savages are in wait, would be fully as dangerous."

To Harry's practical turn of mind, there was another feature that might be considered. "Some time ago you stated, Professor, that it was quite possible we had an island near us as a neighbor, and from which we may have had visitors. If such is likely to be the case, our boat will be the means of enabling us to reach that island, because if they have boats of sufficient size to come here they will be civilized, at any rate."

It will thus be seen from a consideration of all the conditions what determined them to increase the dimensions of the proposed new boat, although it would consume more time than they had originally contemplated.

"Do you remember, boys, that it is now about one year since we left the harbor of New York on our voyage in the training ship Investigator?"

"Yes, and we have been on this island for nine months," answered George. "I can hardly believe it possible."

What might be called spring was now at hand, and as the warm rains had quickened the vegetation, the Professor suggested that it would be prudent to devote some time to the planting of such crops as could be utilized by them. Barley was a crop which grew in sufficient quantities all about them, so that no care need be taken in that direction.

Garden vegetables would be needed most. Wild potatoes grew in many places, but when they were needed search had to be made. Endives, which made excellent greens, could also be found, together with the cassava, and a variety of peas; but aside from the foregoing, nothing else was available.

While talking on this subject one day the Professor remarked: "In my wanderings I found quite a variety of plants that we might utilize in our proposed garden or farm. One of them is a small, triangularly formed, dark brown seed, which you may recognize."

"That," was Harry's answer, "looks something like our buckwheat."

"You are right; I found several varieties; none of them exactly like the kind grown in the States, but we can readily propagate it, so that it will be practically the same."

"How is the propagation done, so as to bring about the change?"

"It is merely a careful selection of the best varieties of the particular plant, and by budding, grafting, or inarching, transmitting the qualities of the good kind to the stalk or tree which bears the inferior kind. That is done with vegetation which is perennial, like fruit trees and the like."



"But how could any of these methods be used with the buckwheat?"

"An entirely different method is used in cultivating vegetation of that kind. You probably have seen wild oats growing here, as in the States. In its wild or native state the grains are so small as to be utterly useless. It is found that by taking this wild plant and changing the soil in which it grows, the seed will finally develop and become larger, until, in time, we get the full grain. The same thing is true in the development of fruit which is full of seeds. The banana in its wild state is full of seeds. By this process of cultivation it has finally become entirely seedless, and the value of the fruit greatly enhanced."

Beyond the Cataract was a low and level stretch of meadow, which the Professor thought was rich and could be readily worked, and it was the field which they determined to devote to agricultural purposes.

In the meantime, the plans for the boat were developed. A description of the recovered after part of the life-boat will make their plans better understood. When they landed on the rock, and its forward part was crushed and washed away, they saw the stern portion lodged in a saddle in the rocks. It was there for an instant only, as the next wave dislodged it, and when it was eventually found, months afterwards, it had caught in the rocks a hundred feet further inland.

The part which they recovered was still in a good condition, but the ruptured portion of the hull was a broken up and splintered mass, so that it would require considerable work to prepare it to receive the bow part which was now to be grafted on.

It had been originally sixteen feet long, with a five-foot beam. Harry's plan was to increase the new vessel to a length of twenty feet, and its extreme breadth six and a half feet, and in order to give greater security and carrying capacity, it should have a depth of two and a half feet.

"How much are you calculating on for the weight to be carried on the new boat?" was the Professor's question.

"I am estimating that the passenger weight will be 400 pounds and the weight of the boat itself at 500 pounds."

"That is a very liberal estimate. Have you considered the mast and sails?"

"That is something entirely beyond my knowledge. I do not know what kind of sail; or how large it shall be; nor the length or size of the masts. If I knew something about the kinds of sails used for vessels I might be able to decide on that as well as the other parts."

"The term ship, as usually applied, has reference to a vessel furnished with a bowsprit and three masts—a mainmast, a foremast and a mizzenmast; and these three masts are each composed of three parts, namely, a lowermast, a topmast, and a topgallant mast."

"The bowsprit is that mast which projects forward from the bow, isn't it?"

"Yes. In small vessels the cutter and the sloop have single masts, the difference being that in the cutter the jib-boom has no stay to support it."

"What's the difference between the jib-boom and the bowsprit; they both project out from the bow of the vessel?"

"The bowsprit projects out only a little forward of the bow, and the jib-boom is attached to the forward end of the bowsprit."

"Well, if we are to have only one mast, should we have a bowsprit?"

"It is not necessary, for the reason that in a small boat the boom, as it is called, to stretch the foot of the sail, runs out directly from the foot of the mast to which it is pivotally hinged."

"Then it would be better to have a single mast and a triangular sail, one side of the sail to be attached to the mast, and one of the other sides to the boom?"

"Yes; excepting that the sail must not be attached to the shaft, but to a cable which is run up the mast."

As the vessel was intended not for speed, but for safety and for ease of management, it was finally decided that the mast should be twenty feet long, and the boom sixteen feet, thus giving a sail area, approximately, of 150 square feet.



CHAPTER XVI

DISCOVERY OF THE SAVAGES' HUTS

While it was true that up to this time they had indirect evidence only of the existence of human beings on the island, several events occurred, at this time, which not only pointed more clearly to such a condition, but they began to feel that leaving the Cataract would be a hazardous thing.

The first incident occurred during one of the hunting expeditions in which the boys engaged. It had been their custom to penetrate the forest below the South River, not very far, it is true, but the sport there was most exhilarating to them after each week's work.

The Professor had always encouraged this. "You have not taken your usual weekly outing," he remarked, "and I feel we ought to have some wild game. If you have time, on your next trip, make it a point to explore the region to the south and west of the falls."

"That section interests me also," answered George. "I have often wished we could go down near the mountain range."

"Couldn't you go with us?" interposed Harry, "and let us make a day of it?"

"I should like to do so," he replied. "But I have good reason for declining at this time, on account of some special work which is attracting my attention, particularly in preparing the instruments we shall need on our voyage."

"That is true," answered George. "But we shall certainly start early enough in the morning to enable us to visit that section, and go far enough to get some idea of what it looks like near the mountain."

"It would be a good idea," suggested Harry, "to take the team along, as far as the river, at any rate, and that will give us an opportunity to ride going and coming. In that way it will help us."

"Yes; and to carry the game," said George, with a laugh.

"If you bag as big game as you did on the last trip, you will need the wagon," replied the Professor.

They were on the way early in the morning, with the guns and plenty of ammunition, and before nine o'clock reached the river. Scarcity of rains had considerably lowered the stream, and they discussed the advisability of fording the team across.

"I am in favor of the idea, if the stream isn't too deep. It seems to be shallow enough."

"Suppose, George, we take out the raft, and try the depth. If we find the animals will have to swim, we had better leave them on this side."

The raft was launched, and it was pushed out with the poles, but before going very far it was seen that the idea was impracticable, and it might be a hazardous operation.

"This won't do. Besides, we may not be able to go into the woods very far, in any event."

"Then," said Harry, "we must select a good place for the team, where they will be in reach of water, and cut plenty of feed for the yaks, as I can see a good half day's sport before us."

"I hope, Harry, we shall not make the mistake of getting lost this time. Let us keep the sun in mind, and watch our bearings at all times."

"The mountains to the south will always be a guide for us. Don't forget that. Then, we shall also know the river is to the north, or in the opposite direction from the mountains."

"So that we may know just where the team is, we must take a note of its location. See the four large trees near the other bank. I think we can remember them, and can see them for some distance."

The raft was pushed across the river, and when it had been properly secured, they began the march directly to the southwest, and within a half hour reached the border line of the great forest.

"Six months ago I would have dreaded to enter such a dense wood as this," said George.

"I was thinking of that, too," replied Harry. "Isn't it singular how we become used to dangers? This is fun now. I can never forget the first long trip we made through the forest to the west of the Cataract. I was frightened at every step, and started at the least noise."

As they entered, the underbrush grew thinner, but the trees were more massive and thicker, and they were so close together, in many places, that little sunlight found its way through the foliage.

"I would like to know, Harry, how we can tell where the mountains are? The trees do not give us an opportunity."

"I suppose we shall have to depend on the sun altogether."

"Yes; it is now forenoon, and we must not forget that the shadow will point in a different direction in six hours from now."

"I have taken note of that," replied Harry. "We are now following our shadow, see? In six hours, which will be about four o'clock, which direction must we go to reach the wagon, judging by the shadow?"

"Let me see; the shadow is to the southwest now. At four this afternoon, it will be about southeast, so, I suppose, we shall have to take a course with the shadow at our right hand."

"Correct! I haven't forgotten that point about the shadows. It's really simple if you stop to reason it out."

Although numerous small animals appeared at frequent intervals, neither had an opportunity to try his skill, because up to that time the boys had been too intent on noting the direction of their route. The course was kept up due southwest, as planned.

"Did you ever see such a gloomy place?" remarked George. "If it wasn't for the chirping of the birds and the chatter of the little animals it would make me feel mighty lonely."

"Ah! there is something!" quietly whispered Harry, as he held out his arm, as though to restrain George. "See that animal slinking away?"

"Where?"

"Almost directly in front. Come closer. See that broken tree?"

"That's an ocelot," exclaimed George.

"Are you sure?"

"Just like the ones we got."

"Oh, this one's much larger."

"Shall we make a try for him?"

"Certainly; if we can get close enough," answered Harry.

The boys moved forward stealthily, using the most convenient trees to hide their movements. The animal was very wary, and the boys knew that the distance was too great to attempt a shot.

"Let us keep on after him. We may get a chance sooner or later," remarked Harry, eagerly.

But the animal kept beyond their reach, and after a half hour it finally forged ahead with such speed that it was soon lost to view, to the great disappointment of the hunters.

"Now, if we can get a glimpse of the sun we shall know what our direction is. This is the most wonderful forest I have ever seen."

"It seems to me we have gone considerably to the right. How far are we from the river, according to your calculations?"

"Well, Harry, I am not good at guessing, but I suppose we have traveled at a pretty lively rate while going after the ocelot. We certainly made two miles trailing him; and it was as much more from the river to the forest. I should say we are fully six miles from it."

"I wish we could get a glimpse of the mountains," answered Harry. "I wonder why the Professor has always been so anxious to investigate this part of the island?"

"That is a mystery to me. It may be merely a natural curiosity."

The boys noted the gradual ascent they were making now, and it was also obvious that the trees were not so thick nor so tall, in comparison with those farther north.

"Do you suppose we are near the base of the mountain?" asked Harry.

"It must be we are near it, or we should not be going up so gradually, as we have done for the last hour."

When several more miles had been added, the woods thinned out perceptibly, and when the clearing was sufficient to enable them to get the first glimpse to the south, Harry remarked:

"Well, there are the mountains, and they seem as far away as when we left the river. Suppose we follow this ridge to the west. You see, there is another forest between us and the mountains."

As they advanced the trees were smaller, and there was every evidence that this was a young forest. There was an abundance of the finest grass, and here they found immense flocks of beautiful pheasants and numerous other birds that were unknown to the boys, and it was not long until they had more than a dozen of different varieties.

"This is getting to be a pretty heavy load," remarked Harry. "I think it would be a good plan to find a place for the game, and then come back and take it as we return."

"Yes; we ought to do that. What time do you suppose it is?"

"It must be past noon, and I am pretty hungry. Why not take our luncheon now?"

"Good idea. Look over to the right. It seems pretty clear there, and the two large trees there will make a good point to aim for on our way back. We can use the log there to rest and spread out our luncheon on," remarked George, as he pointed to the direction of the trees.

He kept looking in that direction intently, as Harry watched him. "What do you see?" Harry asked.

"That looks like a hut."

"So it does," replied Harry, excitedly. "It may be only a large rock, however," he continued.

"No; it doesn't look like a rock to me. Let us move up closer."

The object was fully a thousand feet away, and on a slight crest with few trees about. It was round-topped, very uneven in its outline, which gave it the appearance of a large boulder.

The boys approached cautiously, and as they came nearer, another but smaller object of the same character was noticed to the left.

"That is surely a hut of some kind. See the door at the side of the one to the left?"

"You may be right, Harry, but this seems to be an out-of-the-way place for a village or habitation. You know the Professor stated on one occasion, that even savages were smart enough to plan their homes near running water, and why they should select this place, when they could easily find plenty of water not far away, is something I can't understand."

"Dead sure there is nobody here now. Look at the vines growing across the door opening. Isn't this a find? I wish the Professor could see this."

"Better wait wishing until we see it. We might find something that will surprise us."

"All right, George; let us get up, closer; I am anxious to see the door of the big hut. Let us go around to the other side."

Without approaching the clearing which extended out a considerable distance from the huts, the boys made a circle, until the open door of the large one was in sight, and they were, therefore, directly behind the smaller hut.

"Now let us go up behind this one. If there is anybody in the large one we can easily see him," quietly remarked Harry.

The weeds all about indicated that no one was living there at the time, but they were still too far from the main structure to be able to judge positively.

"What's this?" asked George, kicking at some broad-leaved specimens of vegetables. "See, they are in rows. Some one has had a garden here; that is sure."

"This is certainly getting to be interesting. No; I don't believe there is any one about. Still I don't like the idea of going up to that big hut with the open door."

The boys looked at each other inquiringly. The question was, what to do and how to do it.

"Suppose we fire a shot; that ought to arouse them."

"That would be a good idea, Harry, but I hate to waste the shot. We might call, and see if we can get an answer."

The plan was adopted and after each "Hello!" a slight answering echo came back. There was no response, and they boldly marched up to the open doorway.

There was no light within, other than that through the door, except a little streak from an opening, due to the partially decayed coating of the hut. There was sufficient light, however, to show that this had been occupied by people who were very primitive, as in the interior, at one side, was a pile of bones, scattered about, and a few broken clay vessels, as well as several clam shells, which had been ground to a cutting edge, the examination of which caused the boys to smile.

"Well, what do you think of this? Nothing but bones and dirt everywhere. I suppose it must have been occupied by the savages."

The large hut was circular in form, not exceeding twelve or fifteen feet in diameter, and its extreme height was probably eight feet. It was built of a framework of saplings, the thickest of them not exceeding two inches in diameter, which had been planted in the earth, and then had the tops bent over and bound together.

Smaller branches, or withes, were then run around and interlaced, so as to make the web fairly close, and over this was plastered a species of blue clay, which, when dried and baked by the sun, formed an impervious coating that kept out the rain.

The boys marveled at the construction, because this was the first example of savage architecture they had seen. The smaller hut was distant about fifty feet, similarly made, but smaller in diameter.

"Let us examine the other place. Possibly that will give us some clue," and Harry started across the intervening space, while George was still rummaging about, uncovering the odds and ends and raking them toward the door.

Before Harry reached the hut, George cried out: "Come here, Harry; I have found something." And he held up a scrap of paper. "If the savages have been here they have left something that looks like writing."

Harry was back in an instant, and leaned over George's shoulder as he tried to make out the scrawls on the piece of blackened and crumpled sheet which he was smoothing out. The paper was about four by six inches in size, and evidently a good quality of wrapping paper, known as manilla.

"There are words here, sure enough. Look at this—it must be a name. Yes; can you read it? 'Rogers.' But who has signed it? Can you make that out?"

"Well, if there is one scrap, the chances are there must be some more. Let us get this stuff out of here."

"But be careful, Harry. I found this by the merest accident, and as it is, you will see I have torn it."

A more careful search was now begun, and every scrap was raked out and examined. A brass button was among the things; a buckle; the broken blade of a knife; a little metal disk, which might have been part of a locket case; a steel ring, all rusted and about two inches in diameter.

As these things were successively brought to light, it dawned on the boys that this might well have been the homes of savages, and the articles mentioned were likely taken from captives. The message on the paper, if it could be deciphered, might be the most valuable clue, but they were reserving that for examination later on, when they could have the assistance of the Professor.

The important thing now was to go over every bit of material in both places, and then make a survey of the surrounding country. It set at doubt all questions in their minds about the inhabitants of the country.

The small hut was visited, and here the litter was still more profuse, but after every scrap had been gone over, there was nothing to add to the small accumulation which they had taken from the other hut.

"Shall we go any farther?" asked George.

"It seems to me that this is enough for one day. Before going back, however, let us look all around this place. You know the Professor will be sure to want to know everything about it."

Directly west of the knoll, on which the huts were situated, was a slight declivity. "Let us go down the hill for several hundred feet," said George, as he led the way through the tangled brush.

Within a hundred feet of the hut was a little brook, with the clearest cold water. "I can see why the huts were placed there. Look at that spring."

Within fifty feet of their position was a slightly shelving rock, and below it a bubbling spring flowing upwardly into a semicircular basin formed in the rock.

George ran forward and made a quick survey. "Here is a metal drinking cup, just as they left it. My, but it's heavy!"

"I wonder what it is made of? Here, rub it."

Only a few passes were made over it, when he held it up in astonishment. "Why, it looks like silver."

"So it does," broke in Harry. "But what is this on the side? See those initials: 'A.W.'"

"I must have a drink before I leave this," and Harry removed the little copper cup which he always carried. "What a peculiar water this is! It must be a kind of mineral water."

"Yes," responded George; "that is sulphur water, or it has considerable sulphur in it."

"I wonder if this was a health resort for the savages?" asked Harry, as he laughed.

"Let's start for home at once," remarked George, without noticing Harry's sarcastic fling at the poor inhabitants.



CHAPTER XVII

THE GRIM EVIDENCE IN THE HILLS

The boys secured a convenient pole, over which they slung the braces of game, and started out on the march for the river. It was fully three o'clock before they were ready to start.

"See here, Harry, there is something we have forgotten, and I begin to feel it now."

"What is that?"

"Our luncheon."

"I was so excited and interested that I forgot all about it until now. Why not go back to the spring and take luncheon there?"

"With that water? I'd rather wait until we get to the river."

"Well, let's take something, anyhow. I am mighty hungry. Funny we didn't think of it before."

"Now for our direction. Do you think we can strike the river at the right place?"

"I'll be perfectly satisfied if we strike the river anywhere."

"Then why not go directly north, and we can reach it a mile or two sooner than the way we are now going."

"Good idea! Here we go!"

It was a lucky thing that they decided to take a different course from the river, because they soon discovered that the ridge they were on ran for a long distance almost directly north, and that the woods were not nearly so dense as they were in the course they had followed.

At frequent intervals they came upon new game, and brought down a number of additional specimens, until Harry protested against any further stopping.

"It seems to me we have enough to last a week, and it is getting mighty heavy at this end of the pole."

"Well, it does seem to be an awful distance over to the river. Are you sure we aren't mixed up in the direction?"

"Of course not. The mountains are right behind us, and the shadow at our right. You can't fool me the second time," answered Harry, as he shifted the pole to the other shoulder.

While thus talking they caught the first glimpse of the river, and it was hailed with delight.

"Whenever I get near the old river it feels like home. My! how I would like to put in several days in a further hunt over toward the mountains. I am sure we would turn up something there."

They reached the river a considerable distance above the falls, and without stopping to rest, went down along the bank for a full hour before they came within hearing of the rushing water.

They sat down on the craggy rocks alongside of the stream and took a good rest. "This will be interesting news for the Professor," said George, musingly, as he watched the rushing stream.

"Indeed, it will. I should not be surprised to find that the natives are directly south of us, or rather west of the mountains."

"That may account for the fact that they have never been near our part of the island."

When they took up the load to resume the journey, it was still heavier, apparently, than before, and they were now so thoroughly tired that frequent stops were made, but in another hour they had the satisfaction of seeing the large trees that had been singled out for their guidance.

It was a great relief to deposit the load on the raft, and it did not take long to swing the raft under the wagon and start the yaks on the homeward journey. The Cataract came in sight before six in the evening, and the Professor was on hand to welcome them.

"Did you have a good time?" he inquired; but as he looked over the tailboard and saw the fruit of the hunt, exclaimed: "You must have gotten everything over there."

"Yes, and something else besides that," said Harry in such a tone that the Professor anxiously asked:

"What; have you made any discoveries?"

"Look at that," replied George, as he carefully drew out the discolored paper with the writing on it. "We not only found this, but we discovered some huts—two of them, fully six miles or more southwest of the falls."

The Professor's eyes opened wide. "This is, indeed, interesting. But never mind about telling me now. Let us get the team unhitched and examine this when we get inside. I had a suspicion that the other side of the river would give us some clue."

While Harry and the Professor were putting up the team George prepared several of the pheasants for the evening meal, and they were soon in the oven. By common consent the meal was of more importance than the new finds, and when the dishes were removed the paper was carefully examined.

"If I knew just what was used for the writing, I might suggest something that would bring it out more clearly. It is evident that the writer did not use ink."

"Why do you think so?"

"Simply for the reason that this name, Rogers, which is the most plainly written, has the words only on the surface of the paper. If ink had been used it would have penetrated the fiber, and the writing would thus have been preserved."

"Where did you find the paper?"

"It was among a mass of rubbish, which, on account of the poor light, was raked out to a point nearer the door, so we could examine the material better, and I don't know whether it was with the pile of bones or with the stuff on the other side."

"Was the grass about the hut as high as the grass round about the place?"

"It seemed to be. We made a pretty careful examination all over, so as to give us a fair idea of the condition of things."

"How far was the spring from the hut?"

"Less than a hundred feet."

"By the way," remarked Harry, "we forgot to say that close to the small hut we found some vegetables growing in several rows, and weeds all over the place and between the vegetables."

"Do you think," asked George, "that the vegetable garden is any sign that white people have been living there?"

"It may be; but the lowest savages have usually some form of knowledge about raising and caring for vegetables, so we should not count too much on that. This cup here seems to indicate the presence of some civilized being, whoever he may be."

"It is just as likely, is it not, that the savages may have captured a prisoner who had the cup?"

"That is one solution. This writing is the most important piece of information we have had up to this time. It is not at all likely that the natives would preserve it, so that the only conclusion I can draw from it is, that the one who wrote the message, or the one who got the paper, was at the hut, and now the important thing is to arrive at some sort of idea when, and what the message means."

"It does not seem," remarked Harry, as he carefully scanned the paper, "that we can make out more than a few of the words. Here is the word which looks like 'river.' Yes; I am sure of that."

"And besides that the words 'of' and a capital letter 'B,' and something that looks like 'r-e-n,' which may be simply part of a word," added George.

"As this is simply ordinary wrapping paper, it is likely that it may have no meaning whatever. Still, I have been trying to recall whether anyone on shipboard had a name that these initials would fit. My limited knowledge in that direction does not help me, I confess."

"What do you suppose the cup is made of?"

"That is undoubtedly silver, or some alloy of metals of which silver is the principal part. It is very hard, as you notice. It is certainly a singular thing that a vessel of this kind should be left at the springs, if the owner of it was there, and it is just as remarkable that the natives would permit it to remain there. I now regard the finding of the cup as of far more importance than the paper, because of these considerations."

"Well, the finding of the huts, and these articles, are pretty strong arguments in favor of our purpose to find the people who owned the things we found there," responded Harry.

"But I have also a little news to impart," said the Professor.

"What is it?" asked the boys in concert.

"I have found a companion to the skeleton we discovered on the beach, and also some information about the inhabitants of the island."

"Tell us about it. Where did you come across it?"

"It isn't much of a story, but an hour or so after you left, I felt like taking a little stroll, so I crossed the valley east of us, and skirted the incline beyond, going toward the cliffs fronting the sea. Ever since we found the skeleton I felt that, unless washed out to sea, there might be some other traces of the wreck.

"I was quite unprepared to make any searches along the hillside, except for evidences of minerals, and particularly to note the peculiar outcropping of the rock on this side of the ridge which terminates at Observation Hill.

"The backbone of the ridge is limestone, and after I had reached a certain level I noted, all along, that the rock had remarkably wide cleavages; that is where there had been breaks in the rock the seams opened, and in some places I found recesses fully six feet wide, and thus caverns, sometimes thirty or forty feet in length, would be formed.

"I explored some of them in the hope that it would lead me to a cave of some extent, but in this I was disappointed. Such may be the case, but I have not discovered anything which leads me to believe that there are other caves than the one we explored.

"I entered one of those, which was a long way this side of Observation point, and there, on a rude sort of improvised wooden cot, was a skeleton. I found a half dozen arrows, lying near, but neither a bow nor any other kind of weapon was anywhere in sight.

"The skeleton showed that it was the remains of a tall man, past middle age, undoubtedly, and there was no evidence that he came to his death by any wound which effected a fracture of any of his bones. The cot on which the skeleton reposed was made of pieces of wood, in a complete state of decay, and there was not a vestige of clothing, jewelry or pocket articles at or near the bones.

"I found two of the arrows near one hand, and the others lying about. Here they are. Handle them carefully, as they are decayed, and will readily fall to pieces, unless you use the utmost care. That is my story. I hunted all about the vicinity, hoping that I might find some additional clues, but I was disappointed."

"Do you think he had any connection with the skeleton we found on shore?"

"No; it does not seem likely. My reason for saying so is, that it would take several years for wood to decay, as you see in the case of these arrows, and the cot had the heaviest portions all rotted. In my opinion this skeleton shows greater age."

"Under conditions of that kind, what sort of story could you weave out of it, so as to determine what happened to him?"

"It is decidedly more interesting than our adventure, and about as difficult to gather any information from," answered Harry.

"In my opinion, the man died from starvation, as you say he had no tools or implements of any kind," replied George.

"That may be; but it appears entirely different to me. The man was, undoubtedly, cast ashore, or was shipwrecked. We have evidence that this island is noted for taking in people that way. He may or he may not have had clothing, but in either event, he could not starve in a place like this, with vegetation around him everywhere and at all seasons of the year.

"I am picturing this condition of affairs in my mind: He was, no doubt, out in quest of food, when he was attacked by the natives and escaped from them. He was wounded by them, and when he reached his shelter, removed the arrows, as I found them near his bones. It is probable that his wounds proved fatal shortly after he reached the cave."

"But how do you account for the cot on which he was lying?"

"It would be the most natural thing for him to find a place to shelter himself. That would be the first thing to do; just as he had a place to retreat to, and was fortunate enough to elude his pursuers, who were not aware of the hiding place."

"That seems reasonable," remarked George. "But it seems to point one way sure; that we have a pretty tough lot of people on the island to deal with, and satisfies me that we are going about it the right way, in making the proper preparations for the time when we must meet them."



CHAPTER XVIII

STRANGE DISCOVERY OF A COMPANION LIFEBOAT

The greatest activity was now manifested in every direction. The Professor was here, there and everywhere, taking part in every sort of labor which the different work required. Part of the time he was in the meadow where George was engaged in plowing up an acre of ground for the garden.

It must not be concluded for one moment, that the scheme of eventually leaving the island had been forgotten and that their preparation for planting crops foreboded an indefinite stay.

It will be recalled that the Professor knew what idleness and an unoccupied mind would do to the boys in their situation. He tried in many insidious ways to stimulate the boys to think out and carry forward original work, and in almost every instance he succeeded in doing this in such a way that the boys themselves suggested the work to be done.

Harry was the builder, and the utilizer of the knowledge gained, and George was content at the arrangement which kept him in the workshop with the tools, while he gladly did the most of the outdoor duties.

For two weeks the boys worked without a thought of relaxation, and on this occasion, as on many others, it was incumbent on the Professor to suggest a day of sport. It was the only direction in which he at any time tried to wield the energies of the boys, and from this you may infer how intensely they were interested in the marvelous developments day by day, of which they were the important factors.

"Well," said Harry, "I must confess that I had entirely forgotten our arrangement to devote a day each week to hunting and explorations, and I didn't miss it."

"Nor did I," was George's reply: "I suppose we shall have to go, as I imagine the Professor wants to have some sport," and he laughed at the sly dig which he had given him.

The Professor smiled. "You are right, George, old as I am, I am in for sport, and fun of any kind. Why, I am just as young as you are in feeling and desires, but the difficulty is that getting old is a habit with many people. It gets on their nerves; they get some reminder of old age every day of their lives, and sometimes hourly during the day. When this goes on for three, four, five or ten years, it is too much for the most of humanity. It is taken as an accepted fact that old age means infirmity, and the break comes, not really because the body is weak and worn out, but because the mental state has contributed too much to the idea that they are no longer young and cannot be youthful, and are getting too old to enjoy things that others delight in."

The all-absorbing topic at the evening conference was to determine where the hunting exploits should next take place; whether to the west, where they had witnessed the fight between the bears for the honey tree, or to the other side of the South River, which they called their hunting preserves.

Heretofore, George had been anxious to do all the hunting along the river, but now he kept suggesting the forest to the west, and it eventually turned out that the real reason was on account of the supply of honey giving out; and he had an idea that, as they had not seen any trees with honey indications anywhere else in their wanderings, that would be the proper place to go.

His views prevailed, but it was a two-days' journey, there and back. That was the only objection; and considering that they had not taken a vacation for two weeks, this was not an extraordinary thing to do, notwithstanding the urgent work which they had started on the boat and in the agricultural line.