that night george burke went off his watch at twelve o'clock, and a few minutes after he had been relieved, he did something he had never done before—he deserted his ship. with his shoes and a little bundle of clothes on his head, he very quietly slipped down a line he had fastened astern. it was a very dark night, and he reached the water unseen, and as quietly as if he had been an otter going fishing. first swimming, and then wading, he reached the shore. as soon as he was on land, he dressed, and then went for a lantern, a hammer, and a cold-chisel, which he had left at a convenient spot.
without lighting the lantern, he proceeded as rapidly as possible to the caves. his path was almost invisible, but having travelled that way so often, he knew it as well as he knew his alphabet. not until he was inside the entrance to the caves did he light his lantern. then he proceeded, without loss of time, to the stone mound. he knew that the ladder had been left there, and, with a little trouble, he found it, where shirley had put it, behind some rocks on the floor of the cave. by the aid of this he quickly descended into the mound, and then, moving the foot of the ladder out of the way, he vigorously began to brush away the dust from the stone pavement. when this was done, he held up the lantern and carefully examined the central portion of the floor, and very soon he discovered what he had come to look for. a space about three feet square was marked off on the pavement of the mound by a very perceptible crevice. the other stones of the pavement were placed rather irregularly, but some of them had been cut to allow this single square stone to be set in the centre.
"that's a trap-door," said burke. "there can't be any doubt about that."
and immediately he set to work to get it open.
there was no ring, nor anything by which he could lift it; but if he could get his heavy chisel under it, he was sure he could raise it until he could get hold of it with his hands. so he began to drive his chisel vigorously down into the cracks at various places. this was not difficult to do, and, trying one side after another, he got the chisel down so far that he could use it as a lever. but with all his strength he could not raise the stone.
at last, while working at one corner, he broke out a large piece of the pavement, eight or nine inches long, and found that it had covered a metal bar about an inch in diameter. with his lantern he carefully examined this rod, and found that it was not iron, but appeared to be made of some sort of bronze.
"now, what is this?" said burke to himself. "it's either a hinge or a bolt. it doesn't look like a hinge, for it wouldn't be any use for it to run so far into the rest of the pavement, and if it is a bolt, i don't see how they got at it to move it. i'll see where it goes to." and he began to cut away more of the pavement toward the wall of the dome. the pieces of stone came up without much trouble, and as far as he cut he found the metal rod.
"by george!" said he, "i believe it goes outside of the mound! they worked it from outside!"
putting the ladder in place, he ran up with his lantern and tools, and descended to the outside floor. then he examined the floor of the cave where the rod must run if it came outside the mound. he found a line of flat stones, each about a foot square, extending from the mound toward the western side of the cave.
"oh, ho!" he cried, and on his knees he went to work, soon forcing up one of these stones, and under it was the metal rod, lying in a groove considerably larger than itself. burke now followed the line of stones to the western side of the cave, where the roof was so low he could scarcely stand up under it. to make sure, he took up another stone, and still found the rod.
"i see what this means," said he. "that bolt is worked from clean outside, and i've got to find the handle of it. if i can't do that, i'll go back and cut through that bolt, if my chisel will do it."
he now went back to a point on the line of stones about midway between the side of the cave and the mound, and then, walking forward as nearly as possible in a straight line, which would be at right angles with the metal rod, he proceeded until he had reached the entrance to the passageway which led to the outer caves, carefully counting his steps as he went. then he turned squarely about, entered the passage, and walked along it until he came to the door of the room which had once been occupied by captain horn.
"i'll try it inside first," said burke to himself, "and then i'll go outside."
he walked through the rooms, turning to the right about ten feet when he came to the middle apartment,—for the door here was not opposite to the others,—but coming back again to his line of march as soon as he was on the other side. he proceeded until he reached the large cave, open at the top, which was the last of these compartments. this was an extensive cavern, the back part being, however, so much impeded by rocks that had fallen from the roof that it was difficult for him to make any progress, and the numbering of his steps depended very much upon calculation. but when he reached the farthest wall, burke believed that he had gone about as great a distance as he had stepped off in the cave of the lake.
"but how in the mischief," thought he, "am i to find anything here?" he held up his lantern and looked about. "i can't move these rocks to see what is under them."
as he gazed around, he noticed that the southeast corner seemed to be more regular than the rest of the wall of the cave. in fact, it was almost a right-angled corner, and seemed to have been roughly cut into that shape. instantly burke was in the corner. he found the eastern wall quite smooth for a space about a foot wide and extending about two yards from the floor. in this he perceived lines of crevice marking out a rectangular space some six inches wide and four feet in height.
"ha, ha!" cried burke. "the handle is on the other side of that slab,
i'll bet my head!" and putting down the lantern, he went to work.
with his hammer and chisel he had forced the top of the slab in less than two minutes, and soon he pulled it outward and let it drop on the floor. inside the narrow, perpendicular cavity which was now before him, he saw an upright metal bar.
"the handle of the bolt!" cried burke. "now i can unfasten the trap-door." and taking hold of the top of the bar, he pulled back with all his force. at first he could not move it, but suddenly the resistance ceased, and he pulled the bar forward until it stood at an angle of forty-five degrees from the wall. further than this burke could not move it, although he tugged and bore down on it with all his weight.
"all right," said he, at last. "i guess that's as far as she'll come. anyway, i'm off to see if i've drawn that bolt. if i have, i'll have that trap-door open, if i have to break my back lifting it."
with his best speed burke ran through the caves to the mound, and, mounting by means of the stone projections, he was about to descend by the ladder, when, to his utter amazement, he saw no ladder. he had left it projecting at least two feet through the opening in the top of the mound, and now he could see nothing of it.
what could this mean? going up a little higher, he held up his lantern and looked within, but saw no signs of the ladder.
"by george!" he cried, "has anybody followed me and pulled out that ladder?"
lowering the lantern farther into the mound, he peered in. below, and immediately under him, was a black hole, about three feet square. burke was so startled that he almost dropped the lantern. but he was a man of tough nerve, and maintained his clutch upon it. but he drew back. it required some seconds to catch his breath. presently he looked down again.
"i see," said he. "that trap-door was made to fall down, and not to lift up, and when i pulled the bolt, down it went, and the ladder, being on top of it, slipped into that hole. heavens!" he said, as a cold sweat burst out over him at the thought, "suppose i had made up my mind to cut that bolt! where would i have gone to?"
it was not easy to frighten burke, but now he trembled, and his back was chilled. but he soon recovered sufficiently to do something, and going down to the floor of the cave, he picked up a piece of loose stone, and returning to the top of the mound, he looked carefully over the edge of the opening, and let the stone drop into the black hole beneath. with all the powers of his brain he listened, and it seemed to him like half a minute before he heard a faint sound, far, far below. at this moment he was worse frightened than he had ever been in his life. he clambered down to the foot of the mound, and sat down on the floor.
"what in the name of all the devils does it mean?" said he; and he set himself to work to think about it, and found this a great deal harder labor than cutting stone.
"there was only one thing," he said to himself, at last, "that they could have had that for. the captain says that those ancient fellows put their gold there keep it from the spaniards, and they must have rigged up this devilish contrivance to work if they found the spaniards had got on the track of their treasure. even if the spaniards had let off the water and gone to work to get the gold out, one of the incas' men in the corner of that other cave, which most likely was all shut up and not discoverable, would have got hold of that bar, given it a good pull, and let down all the gold, and what spaniards might happen to be inside, to the very bottom of that black hole. by george! it would have been a pretty trick! the bottom of that mound is just like a funnel, and every stick of gold would have gone down. but, what is more likely, they would have let it out before the spaniards had a chance to open the top, and then, if the ancients had happened to lick the spaniards, they could have got all that gold up again. it might have taken ten or twenty years, but then, the ancients had all the time they wanted."
after these reflections, burke sat for a few moments, staring at the lantern. "but, by george!" said he again, speaking aloud, though in low tones, "it makes my blood run cold to think of the captain working day after day, as hard as he could, right over that horrible trap-door. suppose he had moved the bolt in some way! suppose somebody outside had found that slab in the wall and had fooled with the bar! then, there is another thing. suppose, while they were living here, he or the boy had found that bar before he found the dome, and had pulled out the concern to see what it was! bless me! in that case we should all be as poor as rats! bat i must not stop here, or the next watch will be called before i get back. but one thing i'll do before i go. i'll put back that lid. somebody might find the dome in the dark, and tumble into it. why, if a wandering rat should make a slip, and go down into that black hole, it would be enough to make a fellow's blood run cold if he knew of it."
without much trouble burke replaced the lid, and then, without further delay, he left the caves. as he hurried along the beach, he debated within himself whether or not he should tell captain horn what he had discovered.
"it will be mighty hard on his nerves," said he, "if he comes to know how he squatted and worked for days and weeks over that diabolical trap that opens downward. he's a strong man, but he's got enough on his nerves as it is. no, i won't tell him. he is going to do the handsome thing by us, and it would be mean for me to do the unhandsome thing by him. by george! i don't believe he could sleep for two or three nights if he knew what i know! no, sir! you just keep your mouth shut until we are safe and sound in some civilized spot, with the whole business settled, and shirley and me discharged. then i will tell the captain about it, so that nobody need ever trouble his mind about coming back to look for gold rings and royal mummies. if i don't get back before my watch is called, i'll brazen it out somehow. we've got to twist discipline a little when we are all hard at work at a job like this."
he left his shoes on the sand of the cove, and swam to the ship without taking time to undress. he slipped over the taffrail, and had scarcely time to get below and change his clothes before his watch was called.
