"I think it must have gone right through the hole, señor."
"Then there is an empty space behind!" Harry shouted joyfully. "However," he went on in changed tones, "we must see to José first. That blow may have fractured his arm. Let me look, José. No, I don't think anything is broken, but there is a nasty cut on the wrist. It is fortunate that you were not striking straight down, Dias, for I am sure we have not put anything approaching the strength into our blows, now we are hitting sideways, that we exerted before. You had better go up to Maria, José, and get her to bathe your wrist with cold water, and put on a bandage."
"Now, señor, what shall we do next?"
"Well, now that we know that its weight cannot be anything very great, and that certainly to some extent it can be moved, we will try hammering again at that end. Do you stand three or four feet beyond it, so as to be able to bring your sledge down with all your strength just on the lower corner. I will face you and strike six or eight inches above where you hit. Of course we must both bring our hammers down at the same instant. We shall be able to do that after two or three trials. Stand at the other end of the stone, Bertie, and tell us if it moves at all."
After one or two attempts the two men got to swing their hammers so as to strike precisely at the same moment, and when half a dozen blows had fallen, Bertie said: "It comes out a little at each blow. It is not much, but it comes."
Three or four minutes later he reported, "It is an inch and a half out now, and there is room to get the end of a crowbar in here."
"That is curious," Harry said as he lowered his sledgehammer, and, taking up the candle, examined the end where he had been striking.
"This is sunk about the same distance, Bertie. The stone must work somehow on a pivot."
They now put a crowbar into the end Bertie had been watching, and all three threw their weight on the lever. Slowly the stone yielded to the pressure, and moved farther and farther out. It was pushed open until the crowbar could act no longer as a lever, but they could now get a hold of the inside edge. It was only very slowly and with repeated efforts that they could turn the stone round, and at last it stood fairly at right angles to the wall, dividing the opening into equal parts about two feet four each.
"There is a pivot under it; that is quite evident. It may be a copper ball in the stone below, or it may be that a knob of the upper stone projects into a hole in the lower. However, it does not matter how it works. Here is an opening into something. Dias, will you go upstairs and tell your wife and José to come down? They had better bring half a dozen more torches. Our stock here is getting low, and we shall want as much light as possible. It is only fair that we should all share in the discovery."