One day when they returned from exploring a valley, Harry and his brother, taking their rifles, strolled down an open glade, while Dias and José unpacked the animals. They had gone but a hundred yards when they heard a sound that was new to them. It sounded like the grunting of a number of pigs. Dias was attending to the mules. Harry and Bertie caught up their guns. Presently a small pig made its appearance from among some trees. Harry was on the point of raising his gun to his shoulder when Dias shouted, "Stop, do not shoot!"  
"What is the matter, Dias?" he asked in surprise, as the latter ran up.
 
"That is a peccary."
 
"Well, it is a sort of pig, isn't it?"
 
"Yes, se?or. But if you were to kill it, we might all be torn in pieces. They travel through the forests in great herds, and if one is injured or wounded, the rest will rush upon its assailants. You may shoot down dozens of them, but that only redoubles their fury. The only hope of escape is to climb a tree; but they will keep watch there, regardless of how many are shot, until hunger obliges them to retire. They are the bravest beasts of the forests, and will attack and kill even a lion or a tiger if it has seized one of their number. I beg you to stroll back quietly, and then sit down. I will go to the head of the mules. If the herd see that we pay no attention to them, they may go on without interfering with us. If we see them approaching us, and evidently intending to attack, we must take to the trees and try to keep them from attacking the mules; but there would be small chance of our succeeding in doing so."
 
He and José at once went up to the mules, and stood perfectly quiet at their head. Harry and Bertie moved closely up, laid their double-barrelled guns beside them, and then sat down. By this time forty or fifty of the peccaries had issued from the trees; some were rooting among the herbage, others stood perfectly quiet, staring at the group on the rise above them. Seeing no movement among them nor any sign of hostility, they joined the others in their search for food, and in a quarter of an hour the whole herd had moved off along the edge of the forest.
 
"Praise be to the saints!" Dias said, taking off his hat and crossing himself. "We have escaped a great danger. A hunter would rather meet a couple of lions or tigers than a herd of peccaries. These little animals are always ready to give battle, and once they begin, fight till they die. The more that are killed the more furious do the others become. Even in a tree there is no safety. Many a hunter has been besieged in a tree until, overpowered by thirst, he fell to the ground and was torn to pieces."
 
"What do they eat?" Harry asked.
 
"They will eat anything they kill, but their chief food is roots. They kill great numbers of snakes. Even the largest python is no match for a herd of peccaries if they catch him before he can take refuge in a tree."
 
"Well, then, it is very lucky that you stopped us before we fired."
 
"Fortunate indeed, se?or. By taking to the trees we might have saved our lives, but we should certainly have lost our mules. Both pumas and tigers kill the little beasts when they come across stragglers. And it is well that they do, for otherwise the woods would be full of them, though fortunately they do not multiply as fast as our pigs, having only two or three in a litter. They are good eating, but it is seldom that a hunter can shoot one, for if he only wounds it, its shrieks will call together all its companions within a mile round."
 
"Then we must give up the idea of having pork while we are among the mountains."
 
"Now, are you going to keep me here all day, Dias?" Maria called suddenly. "It seems to me that you have forgotten me altogether."
 
Harry and Bertie could not help laughing.
 
Dias had, on returning to the mules, taken his wife and seated her on a branch six feet from the ground, in order that, should the peccaries attack them, he might be ready at once to snatch up his rifle and join in the fight without having first to think of the safety of his wife. He now lifted her down.
 
The action did even more than what Dias had said to convince Harry of the seriousness of the danger to which they had been exposed, for as a rule Donna Maria had scoffed at any offers of aid, even in the most difficult places, and with her light springy step had taxed the power of the others to keep up with her. These offers had not come from Dias, who showed his confidence in his wife's powers by paying no attention whatever, and a grim smile had often played on his lips when Harry or his brother had offered her a hand. That his first thought had been of her now showed that he considered the crisis a serious one.
 
"I thought Dias had gone mad," she said, as she regained her feet. "I could not think what was the matter when he began to shout and ran towards you. I saw nothing but a little pig. Then, when he came slowly back with you and suddenly seized me and jerked me up on to that bough, I felt quite sure of it, especially when he told me to hold my tongue and not say a word. Was it that little pig? I saw lots more of them afterwards."
 
"Yes; and if they had taken it into their heads to come this way you would have seen a good deal more of them than would be pleasant," Dias said. "With our rifles we could have faced four lions or tigers with a better hope of success than those little pigs you saw. They were peccaries, a sort of wild pig, and the most savage little beasts in the forest. They would have chased us all up into the trees and killed all the mules."
 
"Who would have thought it!" she said. "Why, when I was a girl I have often gone in among a herd of little pigs quite as big as those things, and never felt the least afraid of them. I must have been braver than I thought I was."
 
"You are a good deal sillier than you think you are, Maria," Dias said shortly. "There is as much difference between our pig and a peccary as there is between a quiet Indian cultivator on the Sierra and one of those savage Indians of the woods."
 
"I suppose I can light a fire now, Dias. There is no fear of those creatures coming back again, is there?"
 
"No, I should think not. Fortunately they are going in the opposite direction, otherwise I should have said that we had better stop here for a day or two in case they should attack us if we came upon them again."
 
The next day, as they were journeying through the forest, at the foot of the slopes José gave a sudden exclamation.
 
"What is it?" Dias asked.
 
"I saw a naked Indian standing in front of that tree; he has gone now."
 
"Are you sure, José?"
 
"Quite sure. He was standing perfectly still, looking at us, but when I called to you he must have slipped round the tree. I only took my eyes off him for a moment; when I looked again he was gone."
 
"Then we are in for trouble," Dias said gravely. "Of course it was one of the Chincas. No doubt he was alone, but you may be sure that he has made off to tell his companions he has seen us. He will know exactly how many we are, and how many animals we have. It may be twenty-four hours, it may be three or four days, before he makes his appearance again; but it is certain that, sooner or later, we shall hear of him. Hunters as they are, they can follow a track where I should see nothing; and so crafty are they, that they can traverse the country without leaving the slightest sign of their passage. The forest might be full of them, and yet the keenest white hunter would see no footprint or other mark that would indicate their presence."
 
"What had we better do, Dias?"
 
"We shall probably come to another stream before nightfall, se?or. This we will follow up until we get to some ravine bare of trees. There we can fight them; in the forest we should have no chance. They would lie in ambush for us, climb into the trees and hide among the foliage, and the first we should know of their presence would be a shower of arrows; and as they are excellent marksmen, we should probably be all riddled at the first volley. There can be no sauntering now, we must push the animals forward at their best speed. I will lead the way. Do you, se?or, bring up the rear and urge the mules forward. I shall try and pick the ground where the trees are thinnest, and the mules can then go at a trot. They cannot do so here, for they would always be knocking their loads off."
 
It was evening before they arrived at a stream. Here they made a short halt while they gave a double handful of grain to each of the animals, then they pushed on again until it was too dark to go farther.
 
"Will it be safe to light a fire, Dias?"
 
"Yes, that will make no difference. They are not likely to attack us at night. Savages seldom travel after dark, partly because they are afraid of demons, partly because they would be liable to be pounced upon by wild beasts. But I do not think there is any chance of their overtaking us until tomorrow. The man José saw may have had companions close at hand, but they will know that we are well armed, and will do nothing until they have gathered a large number and feel sure that they can overpower us. They will probably take up the track to-morrow at daylight; but we have made a long march, and can calculate that we shall find some defensible position before they overtake us. José and I will keep watch to-night."
 
"We will take turns with you, Dias."
 
"No, se?or; my ears are accustomed to the sounds of the forests, yours are not. If you were watching I should still have no sleep."
 
The night passed without an alarm.
 
An hour before daylight Dias gave all the animals a good feed of corn, and as soon as it was light they again started. They were already some distance up the mountain, and after eight hours' travelling they arrived at a gorge that suited their purpose. For two hundred yards the rocks rose perpendicularly on each side of the stream, which was but some thirty feet wide. No rain had fallen for some days, and the water was shallow enough at the foot of the cliff for the mules to make their way among the fallen rocks, through which it rushed impetuously. At the upper end the cliffs widened out into a basin some fifty yards across.
 
"We cannot do better than halt here," Dias said. "In two or three hours we can form a strong breast-work on the rocks nearly out to the middle of the stream, where the current is too swift for anyone to make his way up against it."
 
"Are they likely to besiege us long, Dias?"
 
"That I cannot say; but I do not think they will give it up easily. Savages learn to be patient when roaming the forest in search of game. Their time is of no value to them; besides, they are sure to lose many if they attack, and will therefore try to get their revenge."
 
"They may have to give it up from want of food."
 
Dias shook his head.
 
"There are sure to be plenty of fish in the river, and they will poison some pool and get an abundance. With their bows and arrows they can bring down monkeys from the trees, and can snare small animals. However, se?or, we can talk over these things to-morrow. We had best begin the breast-work at once while Maria is cooking dinner, which we need badly enough, for we have had nothing but the maize cakes we ate before starting."
 
Working hard till it was dark, they piled up rocks and stones till they formed a breast-work four feet high on both sides. Some twelve feet in the centre were open. They had chosen a spot where so many fallen rocks lay in the stream that it needed comparatively little labour to fill up the gaps between them.
 
"I thought wood-chopping bad enough," Bertie said as they threw themselves down on the ground after completing their labour, "but it is a joke to this. My back is fairly broken, my arms feel as if they were pulled out of the sockets, my hands are cut, I have nearly squeezed two nails off."
 
"It has been hard work," Harry agreed; "still, we have made ourselves fairly safe, and we will get the walls a couple of feet higher in the morning. We shall only want to add to them on the lower face in order to form a sort of parapet that will shelter us as we lie down to fire, so it won't be anything like such hard work. Then we will fill in the rocks behind with small stones and sand to lie down upon."
 
"They will never be able to fight their way up to it," Dias said.
 
"We need have no fear on that score. The question is, can they get down into this valley behind us; the rocks look very steep and in most places almost perpendicular."
 
"They are steep, se?or; but trees grow on them in many places, and these savages are like monkeys. We shall have to examine them very carefully when we have finished the wall. If we find that it is possible for anyone to get down, we must go up the next gorge and see if we can find a better position."
 
"I suppose you think we are safe for to-night, Dias?'
 
"I don't think they will try to come up through the stream. They have keen eyes, but it would be so dark down there that even a cat could not see. They will guess that we have stopped here, and will certainly want to find out our position before they attack. One or two may come up as scouts, and in that case they may attack at daybreak. Of course two of us will keep watch; we can change every three hours. I will take the first watch with your brother, and you and José can take the next."
 
"José had better sleep," Maria put in; "he watched all last night. My eyes are as good as his, and I will watch with Don Harry."
 
Harry would have protested, but Dias said quietly:
 
"That will be well, Maria, but you will have to keep your tongue quiet. These savages have ears like those of wild animals, and if you were to raise your voice you might get an arrow in the brain."
 
"I can be silent when I like, Dias."
 
"It is possible," Dias said dryly; "but I don't remember in all these years we have been married that I have known you like to do so."
 
"I take that as a compliment," she said quietly, "for it shows at least that I am never sulky. Well, Don Harry, do you accept me as a fellow watcher?"
 
"Certainly I shall be very glad to have you with me; and I don't think that you need be forbidden to talk in a low tone, for the roar of the water among the rocks would prevent the sound of voices from being heard two or three yards away."
 
Accordingly, as soon as it became dark Dias went to the wall with Bertie. José, after a last look at the mules, wrapped himself in a blanket and lay down.
 
"I think I had better turn in to the tent," Harry said; "we have had two days' hard work, and the building of that wall has pretty nearly finished me, so if I don't get two or three hours' sleep to-night I am afraid I shall not be a very useful sentinel."
 
Five minutes later he was sound asleep, and when his brother roused him he could hardly believe that it was time for him to go on duty.
 
"Dias is waiting there. Will you come down?" the latter said. "You were sleeping like a top; I had to pull at your leg three times before you woke."
 
"I am coming," Harry said as he crawled out. "I feel more sleepy than when I lay down, and will just run down to the stream and sluice my head, that will wake me up in earnest, for the water is almost as cold as ice."
 
When he came back he was joined by Donna Maria, and, taking both his shot-gun and rifle, he went forward with her to the barricade.
 
"So you have neither seen nor heard anything, Dias?"
 
"Nothing whatever, se?or."
 
"I have had a good sleep, Dias; we will watch for the next four hours. It is eleven o'clock now, so you will be able at three to take it on till daylight."
 
"I will send and call you again an hour before that," Dias said. "If they attack, as I expect they will as soon as the dawn breaks, we had better have our whole force ready to meet them."
 
So saying Dias went off.
 
"This is scarcely woman's work, Donna Maria."
 
"It is woman's work to help defend her life, se?or, as long as she can. If I found that the savages were beating us I should stab myself. They would kill you, but they might carry me away with them, which would be a thousand times worse than death."
 
"I don't think there is any fear of their beating us," Harry said; "certainly not here. We ought properly to be one on each side, but really I shirk the thought of wading through the river waist-deep at that shallow place we found a hundred yards up; it would be bad enough to go through it, worse still to lie for four hours in wet clothes."
 
"Besides, we could not talk then, se?or," Maria said with a little laugh, "and that would be very dull."
 
"Very dull. Even now we must only talk occasionally; we shall have to keep our eyes and ears open."
 
"I don't think either of them will be much good," she said; "I can see the white water but nothing else, and I am sure I could not hear a naked footstep on the rocks."
 
"It is a good thing the water is white, because we can make out the rocks that rise above the surface. When our eyes get quite accustomed to the dark we should certainly be able to see any figures stepping upon them or wading in the water."
 
"I could see that now, se?or. I think it will be of advantage to talk, for I am sure if I were to lie with my eyes straining, and thinking of nothing else, they would soon begin to close."
 
Talking occasionally in low tones, but keeping up a vigilant watch, they were altogether hidden from the view of anyone coming up the stream, for they exposed only their eyes and the top of their heads above the rough parapet. No attempt had been made to fill up the spaces between the stones, so that, except for the rounded shape, it would be next to impossible to make them out between the rough rocks of the crest. Harry............