With greatly excited curiosity the boys now walked towards the house; but there was a slight delay, for as they approached, Maud and Ethel came running to meet them. 'Is anything the matter with the dam, papa? We have been watching you having such a long talk with the boys. What is it all about?' Mr. Hardy now told them as much as he thought proper of the state of things, and gave them their instructions. The girls, who had no idea there was any real danger, and who had besides an unlimited confidence in their father and brothers, were disposed to look upon it as fun, and Mr. Hardy had to speak quite seriously to be sure that his orders would be strictly attended to. The boys then informed them that the mysterious box was to be opened, and the whole party went up to the house. The box had been placed in the storeroom on the upper floor of the tower, and the boys took up screw-drivers and hammers to open it. The latter tools were not necessary, as the case was very carefully screwed up; and when the top was taken off, it was found that there was an inside case of tin, soldered up. As the boys were cutting through this, they expressed their opinion that, from the extreme care taken, the contents must be very valuable. Still Mr. Hardy would give no clue; and when the case was finally opened, the astonishment of all was unbounded to find that it contained four dozen large rockets and a dozen blue-lights. One dozen of these rockets were ordinary signal rockets, but the rest were covered with strong tin cases. 'Fireworks!' they all exclaimed in intense surprise. 'What have you brought fireworks all this way for, papa?' 'I will tell you, my dears. I knew that the Indians of the Pampas were horse Indians, and the idea struck me, that as they could never have seen rockets, they would be horribly scared at night by them. Rockets, you know, are used in war; and even if the riders are not frightened, it is quite certain that the horses would be horribly alarmed by one or two of these rushing fiery things charging into their midst. I therefore had them specially made for me by a pyrotechnist in London. One dozen, as you see, are ordinary rockets of the largest size; they contain coloured balls, which will give out a most brilliant light. One of them thrown into the air, even where we believe any Indians to be, will light up the plain, and give us a fair view of them. The other three dozen are loaded with crackers. As you see, I have had a strong case of tin placed over the ordinary case; and one of them striking a man, will certainly knock him off his horse, and probably kill him. The roar, the rush, the train of fire, and finally the explosion and the volley of crackers in their midst, would be enough to frighten their horses altogether beyond control. What do you think of my idea?' 'Capital, capital!' they all cried.